The reigning US Open champion, who missed the Australian Open with hamstring issues, was set to face Mackenzie McDonald in the opening round of the ATP 500 event in Acapulco.
Besides his injury frustrations, the teenager has enjoyed an impressive start to 2023, going 8-1 after triumphing in Buenos Aires and being runner-up to Cameron Norrie in Rio.
The latter event saw Alcaraz aggravate a hamstring problem, which has subsequently prevented him from building on that momentum this week.
"Unfortunately I won't be able to play in Acapulco," the Spaniard posted on his social media channels. "I have a grade 1 strain in my right hamstring that will keep me out for several days, according to the tests we did this morning.
"I'm really sad I can't compete here, but now it's time to think about recovering and being ready as soon as possible. I hope to see you all soon!"
Norrie also confirmed he will not compete in Acapulco, the British number one citing fatigue as the reason for his absence.
"Unfortunately, I have to withdraw from Acapulco," he said in an Instagram story. "It's one of my favourite tournaments, so it's really tough for me to withdraw."
The world number two is aiming to become the first player to successfully defend the Barcelona crown since Rafael Nadal won three in a row between 2016 and 2018.
And though run close by Davidovich Fokina, the reigning champion has now reeled off six sets without reply, taking his overall record at the ATP 500 event to 8-1.
The Spaniard, who is now 9-1 against his fellow countrymen since the start of 2022, will play Dan Evans in the last four. The Briton came from behind to defeat 15th seed Francisco Cerundolo 2-6 7-5 6-3.
They are joined by Stefanos Tsitsipas, whose quest for a first title of the campaign continues after a commanding 6-4 6-2 victory over eighth seed Alex De Minaur.
The second seed, who was runner-up at this event in 2018 and 2021, sealed the deal in one hour and 21 minutes to claim his ninth successive win against the Australian.
His reward is a showdown with Lorenzo Musetti, who received a walkover into the last four following Jannik Sinner's withdrawal.
Over in Munich, reigning champion Holger Rune booked his semi-final place with a dominant 6-2 6-4 win over Cristian Garin.
The world number seven, who is now 7-0 in this event, will play Christopher O'Connell. After defeating Alexander Zverev earlier in the week, the Australian qualifier built on his momentum by seeing off Flavio Cobolli 7-6 (7-5) 4-6 6-3.
Second seed Taylor Fritz also advanced in straight sets with a 6-3 6-4 victory over former world number three Dominic Thiem, who overcame eighth seed Marc-Andrea Huesler earlier in the day.
Fritz's semi-final opponent will be Botic van de Zandschulp after the fourth seed saw off Marcos Giron 7-6 (7-5) 6-3.
Several quarter-finals were squeezed into Saturday's schedule alongside evening semi-finals following Friday's ranout, forcing Alcaraz to play twice along with Diego Schwartzman who also progressed to Sunday's decider.
Alcaraz first defeated top seed and 2021 Wimbledon finalist Berrettini in three sets, triumphing 6-2 2-6 6-2 in two hours and two minutes.
The 18-year-old Spanish seventh seed, who reached last year's US Open quarter-finals, backed that up with a straight-sets win over Fognini, 6-2 7-5.
"It means a lot to me," Alcaraz said post-match. "I surprised myself to be able to win two matches in a row in the same day. It's tough to win one match, two is even tougher."
Third seed Schwartzman got past fellow Argentine Francisco Cerundolo 7-6 (7-4) 6-3 in a two-hour-and-two-minute semi-final, having won through earlier in the day 7-6 (7-3) 4-6 6-4 against Pablo Andujar.
The top two seeds will meet in the Delray Beach Open final in Florida after wins by Cameron Norrie and Reilly Opelka on Saturday.
First seed Norrie got past American fourth seed Tommy Paul 6-3 6-3 in one hour and 16 minutes. Norrie had endured a slow start to the calendar year, but will now play for a third ATP Tour title.
Second seed Opelka had a tougher outing, needing three hours to overcome John Millman 7-6 (10-8) 6-7 (3-7) 7-6 (7-4). In a match which only saw two breaks of serve,
Opelka, who won last week's Dallas Open title, sent down 16 aces and won 82 per cent of his first serve.
The 18-year-old struggled for rhythm in the opening set but showed composure to respond by breaking Munar early in the second set and dominating from there.
Alcaraz took the victory in two hours and 15 minutes, saving 10 of 13 break points across the match, while dropping only three games in the second and third sets.
Spaniard Pedro Martinez set up a second-round clash with third seed Diego Schwartzman after a 6-3 6-4 win over Shang Juncheng.
Pablo Andujar Alba also progressed 7-6 (7-2) 7-5 over Pablo Cuevas, while Serbian qualifier Meomir Kecmanovic accounted for local wildcard Felipe Meligeni Rodrigues Alves 6-3 6-0.
At the Delray Beach Open in Florida, Steve Johnson beat South African veteran Kevin Anderson in just over two hours, triumphing 6-2 6-7 (5-7) 6-2.
Oscar Otte got past Yoshihito Nishioka 7-6 (10-8) 6-3 to set up a second-round date with top seed Cameron Norrie, while there were only two breaks across the match as seventh seed Maxime Bressy was ousted by John Millman 6-7 (2-7) 7-6 (7-2) 7-6 (7-3).
Italian veteran Andreas Seppi beat German Peter Gojowczyk 7-5 6-4, while young American Brandon Nakashima comfortably handled Denis Kudla 6-1 6-1.
The tussle between Spaniard Alcaraz and Australia's Alex De Minaur was locked at 2-2 in the first set when play was abandoned for the day, and it was the same score in the last-four clash between Argentinian Diego Schwartzman and Spain's Pablo Carreno Busta.
Both clay-court semi-finals at the ATP 500 tournament are due to resume at 11:00 local time (10:00 BST) on Sunday, followed by the final not before 16:00 (15:00 BST).
Eighteen-year-old Alcaraz has won ATP titles in Umag, Rio de Janeiro and Miami in the past 12 months but has yet to triumph at an event in Spain, and potentially having to play two matches on the same day complicates his task.
On Monday, the fast-rising youngster will become the first teenager since Andy Murray in 2007 to enter the ATP top 10 rankings.
Alcaraz led 6-4 5-3 over the Brazilian wildcard, but was denied a shot at victory as rain interrupted play, which ultimately suspended for the day. Alcaraz's match is scheduled to resume on Wednesday afternoon local time.
The 2022 US Open champion had triumphed last week in Buenos Aires in his first tournament since November following injuries that kept him out of the 2023 Australian Open. Alcaraz is the reigning Rio Open champion.
Cameron Norrie, who Alcaraz beat in the Argentina Open final, progressed with a 7-5 6-1 win over Juan Manuel Cerundolo in one hour and 29 minutes.
Norrie had rallied from a 5-3 deficit in the first set to claim the opening frame, winning 10 of the final 11 games for victory.
Italian veteran Fabio Fognini's charge into the second round was also delayed on the brink of triumph, leading 6-2 5-2 against Chilean qualifier Tomas Barrios Vera when rain intervened.
Fourth seed Francisco Cerundolo won 4-6 6-3 6-3 over Roberto Carbellas Baena while Colombia's Daniel Galan and Peru's Juan Pablo Varillas were also winners on Tuesday.
The 19-year-old phenom has now won all five of his matches in 2023 after winning last week's Argentina Open, and the 2022 Rio champion is now three wins away from defending his title at South America's only ATP 500 event.
Against Fognini, Alcaraz lost the first set despite creating 11 break point opportunities, as his Italian opponent converted all four of his own chances in a back-and-forth battle.
The Spaniard tightened up his service game down the stretch, only allowing Fognini one break point opportunity from the second and third frames combined, and he will now play Dusan Lajovic following his 6-2 6-4 win against Serbian compatriot Laslo Djere.
Chile's Nicolas Jarry is still yet to lose a set in the tournament, following up his impressive upset of third seed Lorenzo Musetti with a 6-2 6-2 triumph over Pedro Martinez.
Jarry will get a crack at another seeded opponent next when he takes on Argentina's sixth seed Sebastian Baez, who emerged victorious 7-5 7-6 (8-6) after two gruelling sets against Peru's Juan Pablo Varillas.
Fourth seed Francisco Cerundolo was eliminated 6-1 4-6 6-1 by Bernabe Zapata Miralles, who will meet Albert Ramos-Vinolas in an all-Spanish quarter-final after he fought off Daniel Elahi Galan 6-2 6-4.
Alcaraz's first-round meeting with Alves was halted on Tuesday due to heavy rain with the 2022 US Open champion leading 6-4 5-3, but the Spaniard clinched victory on Wednesday 6-4 6-4.
The top seed will take on 35-year-old Italian Fognini, who also was made to wait to secure his progress due to the Tuesday rain, eventually triumphing 6-2 6-3 over Chilean qualifier Tomas Barrios Vera.
Second seed Cameron Norrie endured a tough second-round tussle with local Thiago Monteiro, needing two hours and 30 minutes to triumph 7-5 7-5.
The Briton prevailed in one hour and 25 minutes in the first set against the 83rd-ranked Brazilian, while he was broken when serving for the match at 5-4 in the second frame.
Norrie, however, rallied to break straight back before securing victory after successfully serving the match out on the second attempt.
Fifth seed Diego Schwartzman was the major casualty of the day's play, going down 6-1 6-4 to Serbia's Dusan Lajovic in one hour and 29 minutes.
Brazilian veteran Thomaz Bellucci farewelled the ATP Tour after losing 6-3 6-2 to sixth seed Sebastian Baez.
Albert Ramos Vinolas, Bernabe Zapata Miralles and Hugo Dellien were also winners on Wednesday, with the latter progressing into the quarter-finals to face Norrie.
The Spanish teenager is targeting a fifth ATP title of the year, which would move him ahead of Rafael Nadal, having already triumphed in Rio, Miami, Barcelona and Madrid.
Alcaraz is set to move into the top five of the ATP rankings for the first time after seeing off Slovakia's Molcan 7-6 (7-2) 6-1 to reach yet another championship match on his debut in Hamburg.
The top seed broke twice in the opening set but was pegged back on both occasions by Molcan, who was striving to reach a third final of 2022 after finishing as runner-up in Marrakech and Lyon.
But the 19-year-old dominated the tie-break, and found another gear to storm into the final as he made it eight successive sets won this week.
"It was tough," Alcaraz said. "Obviously, [Alex] played really well. The first set was really close; I'm really happy to be able to end the first set playing well.
"I couldn't read the drop shots from him. He was better on the drop shots today, so I was a little bit [frustrated] in the first set.
"In the second set, I think he was down a little bit; he didn't play well. I finished the match with a lot of confidence and played very well."
Standing between Alcaraz and another title is Musetti, who will appear in his maiden ATP final after he overcame Francisco Cerundolo 6-3 7-6 (7-3).
The Italian, who is set to climb into the world's top 50 for the first time, had lost six consecutive ATP Tour matches prior to this week.
But the 20-year-old continued his resurgence; ending the Bastad champion's eight-match winning streak by roaring back from 3-1 down in a second-set tie-break.
Meanwhile, Matteo Berrettini and Casper Ruud will target a third title of 2022 when they lock horns in the Swiss Open showpiece.
Berrettini - a winner in Stuttgart and Queen's before a positive COVID-19 test ruled him out of Wimbledon - registered his 12th successive victory, putting former US Open champion Dominic Thiem to the sword 6-1 6-4 in 78 minutes.
Reigning champion Ruud raced past Albert Ramos-Vinolas; winning five out of seven break points in a resounding 6-2 6-0 triumph.
Top seed Alcaraz only needed an hour and nine minutes to beat Russian Khachanov 6-0 6-2 in a clay-court masterclass on Friday.
The 19-year-old Spaniard moved a step closer to winning a fifth title this year with a dominant performance, breaking the Russian five times in a one-sided contest.
Alcaraz hit 21 winners as Khachanov was given a harsh lesson and the teenager will next face Alex Molcan, who was 2-0 up in the second set after winning the first on a tie-break when Borna Coric retired due to injury.
"I played unbelievable today, probably one of my best matches this year," Alcaraz said of his win against Khachanov. "I'm pretty happy with the performance that I'm playing in this tournament. Yesterday [a victory over Filip Krajinovic] was amazing as well.
"I'm training every day to be solid and at the same time to be aggressive. That is my game."
Francisco Cerundolo and Lorenzo Musetti will contest the other semi-final in Hamburg after beating Aslan Karatsev and Alejandro Davidovich Fokina respectively.
A rejuvenated Thiem is enjoying another hugely encouraging week and will take on Berrettini in his first semi-final of the year following a 6-4 6-3 defeat of Peruvian qualifier Juan Pablo Varillas in Gstaad.
Austrian Thiem has not played in a final since winning his only grand slam at the 2020 US Open, but he claimed his first ATP-level victory for 14 months in Bastad last week and is through to his first semi-final since May 2021 after bossing the baseline battle with Varillas.
It was not all plain sailing for Berrettini, who roared back to beat Pedro Martinez 3-6 7-6 (7-5) 6-1 after the Spaniard was in command of a second-set tie-break at 5-1, but the second seed extended his winning run to 11 matches.
Top seed Casper Ruud got the better of Jaume Munar 7-6 (7-3) 7-6 (7-4), booking a showdown with Albert Ramos-Vinolas, who came through a three-set battle with Nicolas Jarry.
Auger-Aliassime saw off the US Open champion in just 82 minutes as he won 6-4 6-3 to take his unbeaten run to 12 matches.
The Canadian was in irresistible form on Saturday, with his shot placement in decisive moments proving far more consistent and lethal than his counterpart, hitting 23 winners to Alcaraz's eight.
Twenty-two-year-old Auger-Aliassime is still fighting to qualify for the ATP Finals for the first time and victory in Sunday's final will move him up to sixth in the rankings having won each of his two previous tournaments in Antwerp and Florence.
"It's amazing," Auger-Aliassime said. "I never expected it, when I was in Florence three weeks ago, or after the US Open. I'm just really happy that all my work is coming together.
"I've always believed that I can play this way, that I can be consistent in that way, but one thing is to believe and the other is to actually do it. It's nice to feel that way, it's nice to come out on the court and win that many matches in a row. So hopefully this is just the beginning of seeing me play this way."
Rune awaits after the Dane beat Roberto Bautista Agut 7-6 (7-1) 7-6 (10-8) despite being 6-2 down in the second-set tie-break. He will move into the top 20 for the first time as a result of that win.
The final of the Vienna Open will be contested by Daniil Medvedev and Denis Shapovalov, who came through their respective semis in straight sets.
Top seed Medvedev was exceptional against Grigor Dimitrov, with the Russian's serve proving especially important in his 6-4 6-2 win.
Medvedev won 87 per cent of points on his first serve to leave Dimitrov frequently struggling for momentum, and the former world number one recognised that impact.
"The serve is probably the most important shot in tennis," he said. "I was lacking it a little bit this season, I was doing too many double faults. Sometimes in important moments my serve could have been a little bit better. I was working a lot with my coach to try and find this rhythm [again], and so far I'm serving good here. I'm really happy about it and that's also why I'm playing so good."
Shapovalov ultimately romped to an impressive win over Borna Coric.
A tight first set was followed by the Croatian getting bageled as Shapovalov won 7-6 (7-4) 6-0 to reach his second final of the year.
Goffin entered the draw as a lucky loser after squandering two match points to lose his final qualification match against Luca Nardi on Sunday, but he produced a fine display to see off the world number one in one hour and 46 minutes.
The Belgian had to rediscover his composure to take the opener after throwing away a 5-2 lead, but ultimately deserved his straight-sets win over the US Open champion.
Speaking on court after his victory, Goffin said: "I always believe that I have the level to cause some trouble against those guys.
"When you play against the world number one on a big stage, big crowd, the fire inside gives you so much power to play your best tennis because you don't have any choice."
Stefanos Tsitsipas was the only other seed in action in Kazakhstan on Tuesday, and he advanced to the round of 16 by beating home favourite Mikhail Kukushkin 6-3 6-4.
The Tokyo Open also lost its top seed, as Casper Ruud fell to a 6-3 6-3 loss to Jaume Munar, who claimed his first top-10 win since beating Alexander Zverev in 2019.
But the likes of Borna Coric and Nick Kyrgios fared better, claiming straight-sets wins over Thanasi Kokkinakis and Tseng Chun-hsin, respectively.
Wimbledon runner-up Kyrgios only dropped four further points on his serve after being forced to save a break point in his opening service game, racing to a dominant 6-3 6-1 win.
Elsewhere, eighth seed Dan Evans fought back to beat Radu Albot 6-7 (3-7) 6-1 6-4, and Alex de Minaur lost 6-3 6-2 to Kwon Soon-woo.
Defending champion Alcaraz won an all-Spanish contest with Bautista Agut 6-3 7-5 on Pista Rafa Nadal.
Top seed Alcaraz will face another compatriot in the form of Alejandro Davidovich Fokina, who saw off Emil Ruusuvuori, for a place in the last four in his homeland.
Eyeing a third title of the year, 19-year-old US Open champion Alcaraz was a break down at 3-2 in the opening set before winning six games in a row to take the opener.
Bautista Agut broke the teenager's serve twice midway through the second set, but the favourite reeled off nine points in a row to seal victory in an hour and 54 minutes.
Second seed Stefanos Tsitsipas defeated Denis Shapovalov 6-3 6-2, and Jannik Sinner, the fourth seed, battled past Yoshihito Nishioka 6-1 4-6 6-3, but Casper Ruud was beaten by Francisco Cerundolo in straight sets.
Lorenzo Musetti and Dan Evans advanced at the Real Club de Tenis Barcelona-1899 along with Alex de Minaur, who went through with a walkover as Grigor Dimitrov withdrew due to injury.
Meanwhile, there will be no third BMW Open title for Zverev in Munich this week after he suffered a shock loss at the hands of world number 82 Christopher O'Connell.
Australian O'Connell saw off the third seed 7-6 (7-2) 6-4, while defending champion and top seed Holger Rune ousted Yannick Hanfmann 6-3 6-4, and Taylor Fritz got past Marton Fucsovics in three sets.
Lorenzo Sonego was another seed who bowed out, Cristian Garin beating the Italian 6-3 7-6 (7-3).
Alcaraz took just under an hour and 40 minutes to overcome his fellow Spaniard and friend 6-3 6-4, getting 67 per cent of his first serves in and winning 77 per cent of those.
Carreno-Busta struggled to keep the US Open champion at bay, facing 12 break points in all, and although he saved nine of them, his defiance was ultimately in vain.
"It is difficult to play against a friend like Pablo," Alcaraz said on-court after his win on Friday. "Every day we go and have dinner, lunch, together. Every week and we train together, so it is difficult to play against him.
"I also support him and want him to win every match. On court, there are no friends. You have to be focused and go for the match and that is what I did."
Alcaraz will face third seed Felix Auger-Aliassime in the final four after the Canadian defeated Alexander Bublik 6-2 6-3.
The other semi-final will see Roberto Bautista Agut play Holger Rune after the Spaniard beat Stan Wawrinka 7-5 7-6 (7-5) and the Danish teenager defeated Arthur Rinderknech 7-6 (7-0) 6-2.
In Austria, top seed at the Vienna Open Daniil Medvedev beat Jannik Sinner 6-4 6-2 to advance to the last four, where he will play Grigor Dimitrov after the Bulgarian overcame Marcos Giron 6-3 4-6 6-4.
The winner of that contest will face either Denis Shapovalov, who beat Dan Evans 6-3 6-3, or Borna Coric after the Croatian came through against Hubert Hurkacz 6-4 6-7 (2-7) 7-6 (7-5).
The 18-year-old became the youngest winner of an ATP 500 event since the creation of the category in 2009, clinching a 6-4 6-2 victory in one hour and 26 minutes.
Alcaraz, set to climb into the world's top 20 for the first time, captured his second tour-level title after triumphing at last year's Croatia Open.
The Spaniard won five out of six break points, including a crucial one at 4-4 on his way to taking the opening set.
Third seed Schwartzman – champion in Rio in 2018 – was appearing in his second successive final, having reached the showpiece in Buenos Aires last week.
But the Argentinian was unable to compete with the powerful seventh seed on clay, the surface on which Alcaraz could do major damage in the coming years.
Meanwhile, Cameron Norrie landed his third ATP Tour title after beating Reilly Opelka 7-6 (7-1) 7-6 (7-4) in the Delray Beach Open showpiece.
Top seed Norrie had endured a torrid start to the 2022 season, which began for him with four successive defeats.
Meanwhile, Opelka was seeking a second title in as many weeks following his triumph at the Dallas Open.
The American had won six out of six tie-breaks on his way to victory in Dallas, and a further four this week.
But despite the big-serving second seed hitting 25 aces against Norrie, taking his tournament tally to 81, and 46 winners, a total of 33 unforced errors proved costly.
Although he was denied all five opportunities to break as both sets went to a tie-break, Norrie's service game remained solid throughout and just seven unforced errors underlined his strong performance.
Murray has won five singles titles at the event and claimed the doubles title with Feliciano Lopez two years ago just months after undergoing hip surgery.
The three-time major champion last played in Rotterdam in early March, where he was beaten in straight sets by Andrey Rublev in the last 16.
Murray has twice gone on to win Wimbledon after success at the traditional curtain-raiser in London – in 2013 and 2016 – and is relishing the opportunity to play in front of a home crowd again.
"It's been such a difficult time for everyone and it will be great to play in front of home fans in Britain again," Murray said.
"The tournament at Queen's has always meant a lot to me – it's where I won my first ATP match, I've won the singles at Queen's more than any other in my career, and I'll never forget our doubles title in 2019. I can't wait to get back out there."
Lopez is also the reigning singles champion, having beaten Gilles Simon in three sets to become the oldest winner of the event at the age of 37.
The tournament was cancelled last year due to the coronavirus pandemic.
Rublev holds the final automatic qualification spot for the season-ending tournament in London next month following a 6-2 6-1 win over Cameron Norrie.
The third seed was a cut above Brit Norrie, improving his record to 32 victories and just seven defeats this year, which has included three titles.
Shapovalov, meanwhile, beat Stan Wawrinka 6-4 7-5 in a battle between youth and experience, the 21-year-old Canadian winning 84 per cent of his first-service points.
Milos Raonic defeated fellow seed Karen Khachanov 6-1 7-6 (7-1) and will face Borna Coric in the other semi-final, the Croatian having ousted Reilly Opelka in straight sets.
Top seed Alexander Zverev moved into the last four of the Cologne Indoors on home soil, beating South African qualifier Lloyd Harris 6-4 3-6 6-0.
Zverev will come up against Alejandro Davidovich Fokina in his third semi-final of the year after the unseeded Spaniard got past Dennis Novak 6-3 2-6 6-3.
Roberto Bautista Agut and Felix Auger-Aliassime will do battle for a place in the final following wins over Hubert Hurkacz and Radu Albot respectively.
Marco Cecchinato and Lorenzo Musetti will be hoping to contest an all-Italian Sardegna Open in their homeland after advancing to the last four on Friday, along with Serbian duo Laslo Djere and Danilo Petrovic.
The men's tennis tour has scrapped plans to stage four tournaments in China later this year as the pandemic continues to take its toll on the sporting calendar.
Mandatory quarantine rules make it unfeasible for international players and tour officials to travel to the events, including the Shanghai Masters, a top-tier ATP 1000 tournament.
The lucrative Shanghai event had been due to run from October 9-16 and would have featured many of the world's top players.
Also cancelled are the Chengdu Open and the Zhuhai Championships, which were scheduled to begin on September 26, and the China Open, billed for the following week.
The ATP said it had cancelled the three-week China swing "due to ongoing restrictions related to COVID-19".
It marks a third successive year in which the run of tournaments has had to be cancelled, with China last hosting ATP events in 2019, before the pandemic hit.
At the same time as it cancelled the tournaments in China on Thursday, the ATP made provision for its players to keep earning by announcing six new events to take place in September and October.
Those events will be played in San Diego, Seoul, Tel Aviv, Florence, Gijon and Naples, the ATP said, with all at ATP 250 level, the lowest rung of the main tour.
The WTA, which runs the women's tour, announced last December it would be suspending all its tournaments in China due to concerns over the wellbeing of Peng Shuai, a professional tennis player who appeared to allege she had been sexually assaulted by a powerful former government official.
Former doubles world number one Peng has since denied making the accusations, yet the WTA has remained concerned for her safety and freedom.
The Canadian had lost all of his previous eight finals on the tour, not even clinching a set in any of them, but he found the winning formula this time as he beat Tsitsipas 6-4 6-2.
Auger-Aliassime made an emphatic start, breaking Tsitsipas in the very first game and from that point there was no looking back.
The 21-year-old's aggressive style of play had Tsitsipas on the back foot almost throughout and, after claiming the first set, he saw things out with admirable confidence.
He raced into a 5-1 lead in the second set and there were never any signs of nerves on his part, as he avoided facing a single break point over course of the full match.
Auger-Aliassime, who was beaten by Gael Monfils in the 2020 Rotterdam final, said: "It has not been the smoothest road since my first final three years ago.
"It is an amazing day for me to get my first title and especially here. I played my first ATP main draw here a couple of years ago [in 2018], so it is right I won my first title here.
"I have a lot of good memories playing here in front of you, so thank you for making it a special week for me that I will remember for the rest of my life.
"It is the happiest day of my career, and hopefully it is the first of many to come."
Tsitsipas accepted he lost to the better player on the day, bemoaning his struggles when serving.
The world number four won 74 per cent of points on his first serve and 33 per cent on his second – both figures were dwarfed by Auger-Aliassime's 93 per cent and 69 per cent, respectively.
"He played a really good match, producing really good shots and serving well the whole match," Tsitsipas said.
"I wasn't able to serve well at all today. He played very well."
Third seed Auger-Aliassime beat French qualifier Gregoire Barrere 6-4 6-3, while Medvedev earned a 6-2 6-2 victory against Dutchman Botic van de Zandschulp.
Despite being the higher-ranked of the two at present, Canadian Auger-Aliassime has a 0-4 career record against Russian Medvedev.
Those losses include a painful defeat from two sets up in the 2022 Australian Open quarter-finals, and a US Open semi-final knockout blow in the previous season.
It is a record that is all the more surprising considering Auger-Aliassime has wins over Novak Djokovic, Rafael Nadal, Roger Federer, Andy Murray and Carlos Alcaraz to his name.
Auger-Aliassime sits eighth on the ATP ranking list, three places clear of former number one Medvedev, who is relishing their clash on Friday.
Medvedev said on Amazon Prime: "Felix is a top player. He won here last year and played amazing at the end of last season. I'm looking forward to a tough match, and hopefully I can be at my best.
"He's going to take his opportunities. He's going to go for it when he has the chance. So I will need to be at my best and everything has to be better."
Top seed and Australian Open runner-up Tsitsipas was beaten 6-4 6-3 by Jannik Sinner, with last week's Open Sud de France champion winning in an hour and 21 minutes to set up a quarter-final against Stan Wawrinka.
It was Sinner's first career win over a top-three opponent. The Italian held a 0-8 record against such opponents coming into this match.
Fourth seed Holger Rune is also out after retiring hurt while 6-4 4-0 down to Dutch wildcard Gijs Brouwer, who advances to play compatriot Tallon Griekspoor.
Australian Alex de Minaur advanced to the final eight with a 7-5 3-6 6-3 win over American Maxime Cressy, earning a shot at Grigor Dimitrov next.
