The 22-time grand slam singles winner has been off the tour since suffering a muscle injury in Brisbane in January.
He was set to mark his return with a first-round match at the BNP Paribas Open against Canada’s Milos Raonic on Friday.
However in a post on social media, the 37-year-old Spaniard said he is not yet ready to compete.
“It is with great sadness that I have to withdraw from this amazing tournament at Indian Wells,” he said.
“Everyone knows how much I love this place and how much I love to play here. That’s also one of the reasons why I came very early to the desert to practice and try to get ready.
“I have been working hard and practicing and you all know I took a test this weekend but I don’t find myself ready to play at the highest level at such an important event.
“It is not an easy decision, it’s a tough one as a matter of fact but I can’t lie to myself and lie to the thousands of fans.
“I will miss you all and I am sure the tournament will be a great success.”
Nadal has been replaced in the draw by India’s world number 101 Sumit Nagal.
Nadal made his comeback at the Brisbane International in January after spending a year on the sidelines due to a long-term hip problem.
The Spaniard sustained a muscle tear near his hip in his quarter-final defeat to Jordan Thompson in Brisbane, but scans revealed it was not in the same area.
Alcaraz, 19, continued his terrific start to 2023, now boasting 12 wins from his first 13 matches of the year after winning the Argentina Open and reaching the Rio Open final.
But despite the Spaniard's status as the game's top young talent, he came into the contest winless in his three previous meetings against Canada's Auger-Aliassime.
What separated the two this time around was Alcaraz's ability to keep the ball in play. He produced 26 winners with only eight unforced errors, and while Auger-Aliassime was not much worse (24 winners, 13 unforced errors), he committed six double faults.
He is now one match away from reaching the third Masters 1000 final of his career, having won both the Miami Open and the Madrid Open this past season.
Meeting him in the semi-final will be Italy's Jannik Sinner after he prevailed 6-4 4-6 6-4 against hometown hero Taylor Fritz.
In the seesawing contest, Sinner narrowly edged the total point count 94-86 – with both committing exactly 17 unforced errors – but the Italian created nine break point chances compared to Fritz's three.
Since the beginning of the Australian Open, Sinner sports a 14-2 record, with the only losses in that span coming against world number three Stefanos Tsitsipas and world number six Daniil Medvedev.
It will be the sixth meeting between Sinner and Alcaraz, with the Spanish teen taking in a 3-2 edge after a five-set thriller at the US Open.
The 2022 US Open champion triumphed 7-6 (7-4) 6-3 over the Italian 11th seed in one hour and 54 minutes.
Alcaraz is into his maiden Indian Wells final, having lost last year's semi-final to Rafael Nadal, while it is his third career Masters final.
The Spaniard will re-claim the top rank from Novak Djokovic with victory in the decider where he will face in-form fifth seed and 2021 US Open winner Daniil Medvedev who beat Frances Tiafoe 7-5 7-6 (7-4) on Saturday in 108 minutes.
Alcaraz had missed three months due to abdominal and hamstring injuries but continued his excellent return in Indian Wells, after winning the Argentina Open and making the Rio Open decider last month.
The top seed hit 26-14 winners against Sinner, including 17 on his forehand, while he capitalised on the Italian's 50 per cent first-serve percentage, attacking his second serve and converting two of six break points.
Medvedev earned a berth in his maiden Indian Wells decider with his triumph over 14th seed Tiafoe extending his winning streak to 19 games.
The Russian is into an ATP Tour-best fourth final for the season, following victories at the Dubai Tennis Championships, Qatar Open and Rotterdam Open in February.
While Alcaraz is within one victory of the number one ranking, Medvedev can become the first male since Andy Murray in 2016 to win four titles in five weeks.
Medvedev even let slip seven match points against Tiafoe and was broken twice when serving for the match at 5-4 and 6-5 before converting his first match point in the tie-break.
The world number six has maintained his top form despite rolling his ankle in his fourth-round win over Alexander Zverev, showing no signs of injury since.
Alcaraz, 19, kicked off his 2023 campaign with eight wins in a row, including an Argentina Open title, before losing to Cameron Norrie in the Rio Open decider.
He has yet to drop a set at this fortnight's tournament in California, following up his opening win over Thanasi Kokkinakis with another strong showing against 31st seed Griekspoor.
The Spaniard will look to keep his strong form going when he meets Jack Draper in the fourth round, after 21-year-old Draper prevailed 7-6 (8-6) 6-2 in a battle of the Brits against Andy Murray.
Murray, who came into the match with six wins from his past seven outings, had an opportunity to take the match by the scruff of the neck but could not capitalise on a set point before going down in a tight tie-break, before Draper took charge.
California's own Taylor Fritz lived up to his fourth seeding, with the defending champion having little trouble in overcoming Argentina's Sebastian Baez 6-1 6-2, and he will play Hungary's Marton Fucsovics for a spot in the quarter-final.
Fucsovics, after upsetting 16th seed Alex De Minaur in the previous round, got the better of Slovakia's Alex Molcan 6-4 6-2.
Former world number three Stan Wawrinka showed he still has some gas in the tank after a surprise 6-2 6-7 (5-7) 7-5 triumph over world number eight Holger Rune, with the 37-year-old showing what he has learned through competing at the top level for as long as the 19-year-old Dane has been alive.
Jannik Sinner, the 13th seed, successfully navigated the challenge of veteran Adrian Mannarino for a 7-6 (9-7) 6-4 victory, Tommy Paul won his top-20 showdown against Hubert Hurkacz 4-6 6-2 6-4, and eighth seed Felix Auger-Aliassime knocked out Francisco Cerundolo 7-5 6-4.
Spaniard Alcaraz defeated Italian Sinner 7-6 (7-4) 6-3 in California to reach his first Indian Wells final and move within one win of a return to the top of the ATP World Rankings.
Standing in his way is the in-form Medvedev, who owns a 19-match unbeaten run and has won three straight titles.
The two have only met once competitively, with Medvedev winning in straight sets at Wimbledon in 2021 and Alcaraz always wants to challenge himself against the elite on tour.
"I really want to play against the best tennis player in the world," Alcaraz said.
"I always say that if you want to be the best, you have to beat the best, and I would say that Daniil is the best player right now, amazing winning streak.
"For me, it's going to be a really difficult challenge but I'm really prepared for that. I will summon my best tomorrow in the final."
Against Sinner, Alcaraz overcame an opponent with whom he is developing quite the budding rivalry.
It was their fifth career showdown and the first time they had met since Alcaraz won a marathon US Open quarter-final, a match that finished at 2.50am local time – the latest ending at the New York major.
"I would say we're going to have a great rivalry over the years. We are playing in the best tournaments in the world. It's not over here. We are going to play a lot of great matches," Alcaraz added.
"All I can say is I'm really happy with my first final here in Indian Wells.
"Playing against Jannik is never easy. I had to overcome a little bit of problems. I had set point down.
"I knew that I had to increase my level to [beat] Jannik. It was a really close first set. In the second set I put out all the nerves and played more relaxed. I think it was the key of everything."
Medvedev will also play in his first Indian Wells final after defeating Frances Tiafoe 7-5 7-6 (7-4) in the other semi-final.
Medvedev has won in Rotterdam, Doha and Dubai and will be the first man to win four titles in five weeks since Andy Murray in 2016 if he can down Alcaraz.
Against Tiafoe, the Russian put in a great showing but let slip seven match points and was broken twice when serving for the match.
"It was crazy at the end," said Medvedev. "I got super tight. I would say that [after] 6-5, 40-0, I think I got tight at deuce when I was like, 'Oh my god, that's a lot of opportunities missed, this could go not well for me'.
"So, I got really tight, [but] I still managed to continue playing good. The ace [on match point] was a relief, I’m just really happy that I managed not to lose this match."
Despite Medvedev coming into Sunday's decider on a 19-match winning streak, Alcaraz dominated 6-3 6-2 to win in 72 minutes.
Alcaraz's Indian Wells triumph was his third ATP Masters 1000 crown from three finals, not dropping a set in any of those deciders.
The 19-year-old Spaniard went through the Indian Wells Open without dropping a set and reflected that it was a "perfect" fortnight for him.
"It feels amazing to lift the trophy here [and] to recover the number one," Alcaraz told reporters, having reclaimed the top rank from Novak Djokovic due to his victory.
"It has been the perfect tournament. It was a goal for me, this tournament that I really wanted to win. For me, it's amazing."
The lopsided nature of Alcaraz's victory over Medvedev in the final caught many by surprise, hitting 19-4 winners against the in-form fifth seed.
"Honestly I didn’t expect that," Alcaraz said. "I expected a tough match but I played perfect. I said before against Daniil you have to play your best and tactically at your best level as well. I did perfect today. That's why it looks easy but it wasn’t."
Alcaraz added he was delighted to reclaim the number one rank which he had lost after Djokovic won the 2023 Australian Open which he missed due to injury.
Djokovic was unable to participate at Indian Wells due to being unvaccinated for COVID-19, with the pair actually not facing off at any events this year.
Alcaraz returned from abdominal and hamstring injuries last month at the Argentina Open and Rio Open before competing at Indian Wells, while Djokovic was in action at the Dubai Tennis Championships. The next opportunity for the pair to face off as at April's Monte Carlo Masters.
"Novak is one of the best players in the world," Alcaraz said. "That's obvious. I always say, if you want to be the best, you have to beat the best. I really wanted to play against Novak again. We miss him on tour and hopefully to have him back very, very soon."
Alcaraz added: "It feels great to be back on the number one. Of course, every player on the ATP wants to be the number one. For me, it's a dream come true again. Obviously being in front of such great players like Novak, the top player, it's an amazing feeling."
Despite Djokovic being unable to compete at Indian Wells, Medvedev said he felt Alcaraz's return to the top rank was a true number one.
"One hundred per cent," Medvedev said. "It's unfortunate Novak can't play all the tournaments. If you get injured, Rafa is injured for some time, we cannot say if Rafa isn’t injured he would be number one, because we cannot know. Same about Novak.
"For sure if he was able to play last year and this year all the tournaments there is a possibility that the rankings would be different but Carlos is deservedly number one, he won more points than everybody else in the last 52 weeks and he was also year-end number one last year."
Despite Medvedev coming into Sunday's decider on a 19-match winning streak, Alcaraz dominated 6-3 6-2 to win in 72 minutes.
Alcaraz's Indian Wells triumph was his third ATP Masters 1000 crown from three finals, not dropping a set in any of those deciders.
The 19-year-old Spaniard went through the Indian Wells Open without dropping a set and reflected that it was a "perfect" fortnight for him.
"It feels amazing to lift the trophy here [and] to recover the number one," Alcaraz told reporters, having reclaimed the top rank from Novak Djokovic due to his victory.
"It has been the perfect tournament. It was a goal for me, this tournament that I really wanted to win. For me, it's amazing."
The lopsided nature of Alcaraz's victory over Medvedev in the final caught many by surprise, hitting 19-4 winners against the in-form fifth seed.
"Honestly I didn’t expect that," Alcaraz said. "I expected a tough match but I played perfect. I said before against Daniil you have to play your best and tactically at your best level as well. I did perfect today. That's why it looks easy but it wasn’t."
Alcaraz added he was delighted to reclaim the number one rank which he had lost after Djokovic won the 2023 Australian Open which he missed due to injury.
Djokovic was unable to participate at Indian Wells due to being unvaccinated for COVID-19, with the pair actually not facing off at any events this year.
Alcaraz returned from abdominal and hamstring injuries last month at the Argentina Open and Rio Open before competing at Indian Wells, while Djokovic was in action at the Dubai Tennis Championships. The next opportunity for the pair to face off as at April's Monte Carlo Masters.
"Novak is one of the best players in the world," Alcaraz said. "That's obvious. I always say, if you want to be the best, you have to beat the best. I really wanted to play against Novak again. We miss him on tour and hopefully to have him back very, very soon."
Alcaraz added: "It feels great to be back on the number one. Of course, every player on the ATP wants to be the number one. For me, it's a dream come true again. Obviously being in front of such great players like Novak, the top player, it's an amazing feeling."
Despite Djokovic being unable to compete at Indian Wells, Medvedev said he felt Alcaraz's return to the top rank was a true number one.
"One hundred per cent," Medvedev said. "It's unfortunate Novak can't play all the tournaments. If you get injured, Rafa is injured for some time, we cannot say if Rafa isn’t injured he would be number one, because we cannot know. Same about Novak.
"For sure if he was able to play last year and this year all the tournaments there is a possibility that the rankings would be different but Carlos is deservedly number one, he won more points than everybody else in the last 52 weeks and he was also year-end number one last year."
Alcaraz won 6-3 6-3 over Thanasi Kokkinakis in one hour and 18 minutes in his opening match of the event, which also marked his return from a fortnight out with a hamstring injury.
The Spaniard, who reached the semi-finals at Indian Wells last year, could return to the number one ranking with victory at this year's event in the absence of Novak Djokovic.
Alcaraz hit 21 winners against the 94th-ranked Australian, dropping only one point on serve in the opening frame.
Fritz went a set down against 2023 Australian Open quarter-finalist Ben Shelton but eventually prevailed 4-6 6-4 6-3 in one hour and 53 minutes.
Both players were excellent on serve throughout the contest, with Fritz earning a break in the 10th game of the second set to tie up the match, before swooping again in the sixth game of the decisive frame.
Veteran Andy Murray moved into the third round with a 6-4 6-3 win over Radu Albot, with the Briton to take on countryman Jack Draper next. Draper won 6-4 6-2 over 24th seed Daniel Evans.
Murray had been set to face 15th seed Pablo Carreno Busta in the second round, but he withdrew due to a muscle injury, allowing Albot into the draw as a lucky loser. Murray's win was his first in straight sets since October.
Seventh seed Holger Rune won 7-5 6-3 over American Mackenzie McDonald, progressing to face Stanislas Wawrinka after he toppled 26th seed Miomir Kecmanovic 7-6 (10-8) 6-4.
Ninth seed Hubert Hurkacz got past Australian Alexei Popyrin 6-3 6-3, setting up a third-round clash with 17th seed Tommy Paul who won 6-3 6-3 over Jan-Lennard Struff.
Eighth seed Felix Auger-Aliassime won 7-6 (7-5) 6-4 over Pedro Martinez, while 11th seed Jannik Sinner got past veteran Richard Gasquet 6-3 7-6 (7-2).
Last week's Mexican Open champion and 16th seed Alex de Minaur was the highest seed to be knocked out on Saturday after a 6-4 6-2 loss to Martin Fucsovics.
Medvedev came into the decider with 19 straight ATP Tour wins, but Alcaraz made light work of the Russian, winning 6-3 6-2 in 72 minutes.
Alcaraz's triumph means he has three Masters titles from three finals, not dropping a set in any, while it ensured he returns to the rankings' summit ahead of 2023 Australian Open champion Novak Djokovic, who did not participate at Indian Wells.
The 2022 US Open champion has won two of three events since returning after three months out with abdominal and hamstring injuries that forced him to miss the Australian Open.
Alcaraz had labelled Medvedev the "best player right now" in the lead-up to the match, but was on top immediately, opening up a 3-0 lead as he hit 10 winners to the Russian's two in the first frame.
The Spaniard's dominance continued, winning the first 10 points of the second set, taking a 4-0 lead before prevailing with his second match point.
Alcaraz finished with 19-4 edge in the winner count, while Medvedev did not manage one ace for the match, marking the first time that has occurred since February 2020 against Gilles Simon in Marseille.
Medvedev had won in Rotterdam, Doha and Dubai recently and was gunning to be the first man to win four titles in five weeks since Andy Murray in 2016, but was completely outclassed by the 19-year-old.
Only John McEnroe has reached a century of victories in fewer matches, the ATP said, with the American getting there from 131 contests while it took Alcaraz 132 to get to that landmark.
Alcaraz made it 10 wins from 11 matches in 2023 by defeating Tallon Griekspoor 7-6 (7-4) 6-3 on Monday at the California tournament.
The Spanish prodigy last year won the US Open and in doing so became the youngest men's world number one, with Novak Djokovic having since clawed back top spot.
Victory over Griekspoor made Alcaraz the third men's tour player born after 2000 to claim 100 tour wins, after Jannik Sinner and Felix Auger-Aliassime, said OptaAce.
The youngster's first tour-level win came against fellow Spaniard Albert Ramos-Vinolas at the 2020 Rio Open, with the then 16-year-old wrapping up a 7-6 (7-2) 4-6 7-6 (7-2) at 3am local time.
The latest victory was his 24th at ATP 1000 level, going past Djokovic on the all-time ranking for wins at that elite tier by players before turning 20.
Alcaraz trails Denis Shapovalov (25) and Rafael Nadal (49), in that regard, but the chances are he will soon only trail Nadal, whom he cannot catch.
With his 20th birthday coming up in May, Alcaraz can substantially add to his ATP 1000 wins before leaving behind his teenage years. He will be looking to go further at Indian Wells and then rack up more victories in Miami, Monte Carlo and Madrid.
He will turn 20 on May 5, during the Madrid tournament where he is the defending champion.
Reflecting on his time on tour so far, Alcaraz said: "A lot has happened since that first ATP win. I'm really proud of myself to have my 100th win on the tour, in like 132 matches.
"I saw I was the second player in history with less matches to be able to get to 100 wins. I'm really proud of myself about that."
Alcaraz has a win percentage of 70.6 at ATP 1000 events in his fledgling career. Only three players with 10 or more matches in ATP 1000 events as a teenager have a higher percentage of success: Andre Agassi (90.9 per cent), Rafael Nadal (84.5) and Jim Courier (72.7).
Standing in the way of Alcaraz making an immediate improvement to his record is another emerging young talent, the 21-year-old British player Jack Draper.
They will meet in round four at Indian Wells on Tuesday, with Draper having sunk the hopes of compatriot and three-time grand slam winner Andy Murray on Monday to reach that stage.
"I know he's a really good player," said Alcaraz, who won his one previous meeting with Draper, a tight three-setter in Switzerland last year.
"I mean, he's playing well. He has beaten great opponents like [Dan] Evans and Andy. I know that I'm going to have to play my best, give my 100 per cent on court. I played against him in Basle [and won] 7-5 in the third, I think. It's going to be a really tough match and I'm going to enjoy it."
It is the latest in a string of hard-fought wins for Murray, who has played the maximum number of sets in each of his past 10 victories dating back to the Gijon Open in October, including a pair of five-setters at the Australian Open.
Etcheverry started strong, fresh off his first ever ATP final at the Chile Open, but committed more unforced errors (21) than winners (17) in the second and third sets combined.
Fellow Great Britain representative Jack Draper was far more comfortable in his 6-1 6-1 demolition of Switzerland's Leandro Riedi, booking an all-English clash against Daniel Evans in the second round.
Former world number three Stan Wawrinka prevailed 6-4 1-6 6-1 against Aleksandar Vukic, but Vukic's Australian compatriot Thanasi Kokkanakis flew the flag with a 6-4 6-1 triumph over hometown talent Brandon Holt.
In a better result for the Americans, Mackenzie McDonald breezed past Filip Krajinovic 6-3 6-0 in just 63 minutes, and rising 20-year-old Ben Shelton had no problems in his 6-4 6-1 win over Fabio Fognini in 72 minutes.
Argentina's Guido Pella ground out 3-6 7-5 6-2 comeback in his South American clash against Brazil's Thiago Monteiro, and Germany's Jan-Lennard Struff did the same in his European showdown against France's Quentin Halys, taking it 1-6 6-3 6-3.
Djokovic won his first match back on the ATP Tour since missing the Australian Open on Monday, beating Lorenzo Musetti in the round of 32 at the Dubai Tennis Championships.
The men's world number one had not played a competitive match since early December and was last month deported from Australia on the eve of the Australian Open.
That decision was a result of Djokovic opting not to join the majority of his tennis peers in getting vaccinated against COVID-19 and amid controversy over how he handled getting the virus himself in December.
He showed no signs of rust as he eased to a 6-3 6-3 win over Musetti in just 74 minutes in his first match of 2022, hitting five aces, winning an impressive 71 per cent of his second serves (17 out of 24) and saving all seven break points he faced against his Italian opponent.
However, at a press conference following his victory, Djokovic admitted he is currently unable to enter the United States, and is therefore on course to miss March's prestigious Indian Wells Masters tournament.
"As of today, not. I can't go, I can't enter the United States," he said.
"As of today I'm not able to play. But let's see what happens. I mean, maybe things change in the next few weeks."
Djokovic has been included on the entry list for Indian Wells despite the tournament requiring all players are vaccinated against COVID-19.
Images of Djokovic do not appear in any of the tournament's build-up social media posts nor on the website's promotional announcement, while his entry-list inclusion was little more than a footnote – though did include him.
The statement read: "A power-packed line-up of ATP top-10 players will join [Rafael] Nadal in looking to put together a breakthrough performance in Tennis paradise.
"2021 US Open champion and 2022 Australian Open finalist Daniil Medvedev (world no. 2), 2021 ATP Finals winner Alexander Zverev (world no. 3), and 2021 French Open finalist Stefanos Tsitsipas (world no. 4) will each be in search of their maiden title in the desert.
"Reigning BNP Paribas Open champion Cameron Norrie (world no. 13) will look to replicate his extraordinary 2021 title run, in which he won his first Masters 1000 crown.
"World no. 1 and five-time Indian Wells champion Novak Djokovic is also on the tournament entry list."
First up, world number six Sakkari took on Ukrainian Elena Rybakina, prevailing 7-5 6-4.
Rybakina won the first three games of the match, working her way to an early 4-1 lead, before her Greek opponent rattled off six of the next seven games to claim the first set.
Sakkari again faced adversity early in the second set, coming back from 40-0 down in the second game to hold serve, before breaking the very next game to pinch the match-winning lead.
Azarenka, also a winner in 2012 and 2016, had to come back from a set and a break down in the semi-final, and for a while looked like good preparation for the battle that Badosa provided.
But in the end Badosa prevailed 7-6 (7-5) 2-6 7-6 (7-2) after three hours, four minutes on court, securing only her second title in what was just her second final of the season while becoming the first Spanish woman to claim the title in Indian Wells.
A highly competitive start saw a combined total of nine break points go to waste in the first four games alone, and when Azarenka did finally lose a service game to go 4-3 down, she emphatically hit back at the first time of asking.
She had no option but to repeat that feat soon after when Badosa broke again to take a 6-5 lead, and she duly obliged to set up a tie-break.
But Badosa got the better of two-time grand slam champion Azarenka in the tie-break, despite the latter overturning a four-point deficit to go level at 5-5.
Azarenka appeared re-energised at the start of the second set, though, charging into a 3-0 lead inside 11 minutes, her level of intensity suddenly leagues ahead of her opponent's.
Badosa only showed brief glimpses of her ability and Azarenka had few issues levelling the match, her class on full display in the fifth game as she read a wide drop shot and replied with a sensational cross-court effort.
After such a colossal fight to get back on level terms it was perhaps to be expected that Azarenka would drop off a little early on in the decider, but a bad miss from Badosa allowed the Belarussian to recover from a break and she consolidated to tie the set at 2-2.
The pair continued to slog it out thereafter with neither woman giving an inch, Badosa's often-brutal power countered nicely by Azarenka's athleticism.
But Badosa was her own worst enemy as she overhit two shots to allow Azarenka to get what looked likely to be the decisive break, but the 32-year-old failed to serve out the match and, perhaps predictably, a tie-break ultimately beckoned.
Badosa's energy reserves suddenly looked far deeper than her opponent's as she moved her around the court with almost surgical precision, her eventual 7-2 win in the tie-break speaking to the ferocity she displayed to win the comfortably biggest title of her career to date.
Gauff could not let loose quite the same this week, as she battled through to the Indian Wells Open quarter-finals on Tuesday, coming back in the decisive set to beat Rebecca Peterson 6-3 1-6 6-4.
The world number six will be hoping to remain unbeaten as a 19-year-old when she faces second seed Aryna Sabalenka in California, where a win for the home favourite would have everyone jumping for joy like in 2012, when Gauff was filmed singing and dancing to Carly Rae Jepsen's hit single Call Me Maybe at Flushing Meadows.
"I think that was the only Kids' Day," Gauff recalled.
"But I remembered it because Call Me Maybe was trending, and I knew that video existed.
"I thought that my mom would have it because she keeps track of everything, but it was really my dad who has it, so that's why we never found the video because I never thought to ask him."
An eight-year-old Gauff at the Arthur Ashe Stadium would have had no idea that she would reach the competition's quarter-finals just a decade later, and she is now ranked seventh in the world.
Her rise has continued at Indian Wells, with a last-eight appearance already her best-ever run in the event.
Gauff added: "I just love that video and just the whole full-circle moment.
"Call Me Maybe was the song at that time. Even now I still love when they play it.
"I don't know whose number I was trying to get, I think I was eight years old. But I'm going to use that pickup line now!"
Australian Open champion Sinner had won 16 straight matches to begin the year – and 19 in all stretching back to last season – but the number three seed had no answer to the Spaniard after winning the first set.
Defending Indian Wells champion Alcaraz was broken twice after a three-hour rain delay as Sinner raced to a 6-1 first set victory.
But having faced deuce on his opening service game of the second set, the Spaniard grabbed the initiative with an early break.
He saved break points in successive games and served out to level the match.
Alcaraz, who would have surrendered the world number two spot to Sinner with a defeat, again broke early in the deciding set.
He dropped just three points on his serve, rattling off five straight games to lead 5-1, clinching victory on his third match point in just over two hours.
“I stayed strong mentally,” said Alcaraz. “I think that’s a really important part in this game. You have to be strong mentally if you want to overcome these kind of matches, a set down against someone that’s playing an unbelievable game.
“I changed my style a little bit, I changed my game a little bit and I think it worked very well. I’m really happy to beat Jannik and be in the final again.”
The Spaniard, bidding to become the first player to defend the title since Novak Djokovic in 2016, won 6-3 6-3 in an hour and a quarter.
Hungarian Marozsan, 24, came into the match with a rare winning head-to-head record against Alcaraz, having beaten him on the Rome clay last year in their only previous meeting, one of the shock results of the season.
The Wimbledon champion quickly went about taking his revenge, winning four games in a row from 3-2 down to take the first set.
A solitary break for 4-2 in the second proved enough to wrap up the match and book a last-eight meeting with Alexander Zverev.
“Honestly I was nervous before the match, playing against someone who beat you, let’s say easily, it was difficult for me to approach the game,” Alcaraz said in his on-court interview.
“But I’m happy with the win. Today I knew better what I needed to do than in Rome.”
Zverev took down Australian Alex de Minaur after he lost the first set before coming back to win 5-7 6-2 6-3.
Australian Open champion Jannik Sinner continued his stellar start to the year, recording his 18th straight win in a victory over American Ben Shelton 7-6 (4) 6-1.
Stefanos Tsitsipas, the 11th seed from Greece, was on the end of an upset as he slipped to a 6-2 6-4 defeat to Czech youngster Jiri Lehecka.
Clijsters remains winless since coming out of retirement on the WTA Tour, falling 6-1 2-6 6-2 to Katerina Siniakova on Thursday.
A four-time grand slam champion, the 38-year-old Clijsters has lost all five of her singles matches since her return last year.
"I think overall, there's definitely moments where I'm feeling really good out there, and there's moments where I feel too inconsistent," Clijsters – a winner at Indian Wells in 2003 and 2005 – told reporters.
"That's part of this process in general, it's not going to be a smooth ride, and that's what I'm going to try to improve every time I'm out there."
World number 53 Siniakova converted six of nine break points on Clijsters' serve and moved on to face 10th seed Angelique Kerber at the WTA Premier 1000 event.
GOLUBIC HOLDS OFF VONDROUSOVA
The day's only duel between top-50 players saw world number 46 Viktorija Golubic outlast 37th-ranked Marketa Vondrousova 6-1 4-6 6-3.
Both players struggled with their own service games, combining for three aces and 17 double faults, but it was the Swiss who managed to convert on eight of 14 break-point chances and come out on top.
It was Golubic's first win against a player in the top 50 since joining those ranks herself in July; she had been 0-3 against them since then.
GARCIA RALLIES PAST FLIPKENS, RISKE GETS RARE INDIAN WELLS WIN
Caroline Garcia fought back to defeat Kirsten Flipkens 5-7 6-4 6-0 in a match that took two hours, nine minutes to complete, firing seven aces and winning 71.2 per cent of points on her first serve.
The Frenchwoman, who had been upset by qualifiers at her two previous tournaments in Ostrava and Chicago, meets 15th seed Coco Gauff in the second round.
Alison Riske celebrated a victory for just the second time in seven trips to Indian Wells, cruising past qualifier Liang En-shuo 6-2 6-2 to set up a second-round matchup against 16th seed and former US Open champion Bianca Andreescu.
The four-time grand slam champion is on the comeback trail after reversing her 2012 retirement last year.
Clijsters, 36, earlier this month was beaten in straight sets by Garbine Muguruza at the Dubai Tennis Championships on her return to the court.
The Belgian is a two-time Indian Wells champion and is also set to play at Monterrey before heading to California.
It was also announced by tournament organisers on Thursday that both Novak Djokovic and Rafael Nadal have been given wild cards to play doubles at Indian Wells.
World number one Djokovic is set to team up with Viktor Troicki after they were part of Serbia's ATP Cup-winning squad at the start of the year.
Nadal, second behind Djokovic in the singles rankings, will play with compatriot Marc Lopez, with whom he won gold at the 2016 Olympic Games.
The American made a strong start to the year with her impressive run to the fourth round of the Australian Open, where she beat defending champion Naomi Osaka.
Those exploits from Gauff followed up on her breakout second half of the 2019 season.
She burst onto the scene with a run to the last 16 at Wimbledon last year and went on to claim her first WTA Tour title in Linz.
Gauff's year-end ranking in 2018 was 686 and she had risen to 68 by the end of 2019.
Other WTA Tour results and points dropped for rival players saw Gauff reach a new peak of number 49 in Monday's latest version of the WTA rankings, the first time she has made the top 50.
The last 15-year-old to reach the top 50 wasSesil Karatantcheva, who achieved the feat in the week of August 1, 2005.
Gauff will look to continue her ascension when she returns to action at the Indian Wells Open next month, one of the biggest WTA tournaments outside of the grand slams due to its Premier Mandatory status.
She turns 16 in March, which means the current age restrictions which apply on the number of tournaments she is able to play will ease.
Australian Ash Barty remains top of the WTA rankings, while Bianca Andreescu is up to fourth, with Australian Open winner Sofia Kenin now in fifth position.
Belinda Bencic has fallen five places to ninth after her first-round loss at the Dubai Tennis Championships, an event she won last year.
