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.
The highly rated Spanish teenager eventually downed the German wildcard 3-6 6-1 7-6 (7-3).
Kuhn, ranked 259 in the world, was aggressive early on against Alcaraz, and was rewarded with the first set.
But the 19-year-old – playing as top seed in an ATP Tour event for the first time – rallied to ease through the second set, before being made to work much harder to clinch the win on a tie-break.
Alcaraz will now play Filip Krajinovic in the second round after the Serbian also won in a third-set tie-break against Sebastian Baez 6-1 4-6 7-6 (8-6).
Three seeded players crashed out on Tuesday in straight sets, with third favourite Diego Schwartzman losing against Emil Ruusuvuori 7-5 6-4, sixth seed Nikoloz Basilashvili beaten by Aslan Karatsev 6-4 6-0, and eighth seed Holger Rune going down 7-6 (10-8) 7-5 to Tallon Griekspoor.
Fourth seed Pablo Carreno Busta eased through against Luca Nardi 6-2 6-1, while there were also wins for Fabio Fognini, who sealed his 400th career victory, as well as Daniel Elahi Galan, Borna Coric and Francisco Cerundolo.
At the Swiss Open in Gstaad, sixth seed Cristian Garin lost 6-3 6-4 to Yannick Hanfmann and seventh favourite Hugo Gaston fell to Dominic Thiem despite winning the first set, losing 1-6 6-1 7-6 (9-7).
Elsewhere, Frenchman Richard Gasquet beat Roberto Carballes Baena 7-5 6-4, while his compatriot Benoit Paire retired hurt when a set and a break down against Elias Ymer.
A tight game between Swiss pair Dominic Stricker and Marc-Andrea Huesler saw the former prevail 6-7 (2-7) 7-6 (7-2) 6-4, and an all-Spanish affair was similarly close as Jaume Munar defeated Bernabe Zapata Miralles 6-3 3-6 7-5.
There were also wins for qualifiers Juan Pablo Varillas and Nicolas Jarry against Lorenzo Sonego and Thiago Monteiro respectively.
Thiem earned his first tour-level win in 14 months by downing Emil Ruusuvuori on his Bastad debut, before reaching his first quarter-final of the season by overcoming Roberto Bautista Agut on Thursday.
The Austrian battled to a 7-6 (7-5) 3-6 6-4 victory over the fourth-seeded Bautista Agut, picking up his first top-20 win since beating Novak Djokovic at the ATP Finals in 2020.
Sebastian Baez, who defeated Alejandro Davidovich Fokina in straight sets, awaits in the next round and former world number three Thiem is ready for the task.
"The win against Emil gave me confidence that I can compete against the best players in the world and today against Roberto," said Thiem, the 2020 US Open champion.
"He is always such a tough opponent. I was expecting and hoping it would be a close match. Then when I won the first set in the tie-break I said 'Hey, I can win today.'
"I had the belief until the end of the match and the third set was really good. It is a process. I beat Ruusuvuori and today I beat Bautista Agut.
"Two really top opponents, so if I can beat them I am definitely back. I am into the quarters of a really strong tournament, so I am happy. It is a process, but I am going the right way."
Second seed Andrey Rublev was made to work for his 7-5 4-6 7-6 (7-2) victory over Federico Coria and will meet Laslo Djere, who defeated Marc-Andrea Huesler in straight sets to reach the quarter-finals.
Meanwhile, Auger-Aliassime resumed his match with Jason Kubler in Newport that was suspended due to bad light on Wednesday with a slight advantage but fell to a 4-6 6-3 7-6 (7-4) second-round loss.
That marked a first top-10 victory for Kubler, continuing his fine 2022 season that saw him achieve his best major result at Wimbledon, where he reached the fourth round at the All England Club.
Fourth seed Maxime Cressy is yet to drop his serve at the tournament but needed to survive a first-set scare against fellow American Steve Johnson to triumph 6-7 (3-7) 6-4 6-4.
Second favourite John Isner will meet Cressy in the semi-finals after battling past fifth seed Benjamin Bonzi 6-7 (2-7) 7-6 (8-6) 7-6 (7-5).
His fellow defending champion, Aryna Sabalenka, routed Lesia Tsurenko 6-0 6-0 while 16-year-old Mirra Andreeva recovered from 5-1 down in the deciding set to beat Diane Parry.
It was generally a good day for the big names, with Coco Gauff, Jannik Sinner and Stefanos Tsitsipas also winning.
Picture of the dayTweet of the dayRod back in his houseOutfit of the dayFallen seeds
Women: Beatriz Haddad Maia (10), Lesia Tsurenko (28)
Men: Ben Shelton (16), Sebastian Baez (26), Sebastian Korda (29), Tomas Martin Etcheverry (30)
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Britain’s final singles hope, Cameron Norrie, takes on Casper Ruud for a place in the fourth round.
Chinese players take centre stage in the day on Rod Laver Arena, with Zheng Qinwen meeting Wang Yafan before Shang Juncheng faces Carlos Alcaraz.
Iga Swiatek is first up in the night session against Czech teenager Linda Noskova, while Daniil Medvedev meets Felix Auger-Aliassime.
The Argentinian put in a powerful performance to ease past the American fifth seed, winning 6-3 6-2 in Portugal in just 74 minutes.
It was a fast start from Tiafoe, breaking Baez in the opening game, before the 21-year-old secured back-to-back breaks of his own in the fourth and sixth games to edge ahead, ultimately taking the first set.
The second set started evenly, but from 2-2, Baez put his foot down, again breaking consecutive Tiafoe service games, before serving out for the title.
The first serve was the difference for Baez, making 64 per cent of his compared to Tiafoe, who managed just 39 per cent.
Baez was also more effective when he needed his second serve, winning 61 per cent of points, with his opponent winning only 39 per cent from his own second serve.
In the fourth ATP Tour final of his career, Baez secured his second title, showing a slight edge both in his service game and with his returns.
He rattled through the first set in just 31 minutes, winning 17 of his 20 total service points (85 per cent), while Coria could only convert at a 48 per cent rate (11 of 23).
Coria tightened things up in the second set and turned the tide, winning 81 per cent of points on his serve while Baez plummeted to 61 per cent, not allowing a single break point opportunity.
Each player created two break point chances in the deciding set, and while Coria failed to convert either, Baez got the job done at the first attempt, jumping out to an early lead and serving it out the rest of the way.
Coria shot himself in the foot with five of the six total double faults, while Baez served the only ace of the match.
The 22-year-old Baez, who entered the contest ranked 47th in the world, will now climb into the top 40 as he edges closer to his career-best ranking of 31st.
French qualifier Barrere and US veteran Isner were forced indoors by the adverse weather threat in New Zealand, with the entire Tuesday schedule taking place on inside courts and without spectators.
Despite Isner rifling down 28 aces to move 10 away from becoming the first man to post 14,000 in ATP tour and grand slam events, Barrere stuck with him and pulled off a 6-7 (3-7) 7-6 (7-5) 6-3 victory.
He snatched the only break of the match in game eight of the deciding set, before serving out for victory, with the world number 88 firing down 10 aces himself across the contest.
Argentine seventh seed Sebastian Baez also fell at the last-32 stage, bowing out 7-6 (7-1) 6-1 to American wildcard Ben Shelton.
Serbian Laslo Djere set up a second-round clash with top seed Casper Ruud by edging out Spain's Jaume Munar 3-6 6-1 7-6 (7-4), while Czech Jiri Lehecka will face second seed Cameron Norrie next after sinking Brazilian fellow qualifier Thiago Monteiro 6-3 7-5.
Ruud and Norrie received first-round byes.
At Adelaide International 2, American eighth seed Tommy Paul battled past Australian Christopher O'Connell 6-4 7-5, setting up an appetising second-round clash with Britain's Jack Draper, who won through on Monday.
There was a home success for the Australian crowd to cheer, though, as qualifier John Millman, who beat Roger Federer at the 2018 US Open, this time dug deep for a 4-6 6-3 7-6 (8-6) win against Spain's Albert Ramos-Vinolas.
Federico Coria, seeded sixth, overcame reigning champion and 2021 runner-up Albert Ramos-Vinolas 6-4 7-6 (7-2) after over two-and-a-half hours of action.
The world number 67, who is into his second ATP Tour-level final and is set to rise into the top 50 of the rankings, has dropped just a single set in the tournament.
Sebastian Baez, eight years Coria's junior, is aiming for his second title after winning in Estoril last year.
The 22-year-old fourth seed defeated Hugo Dellien 6-4 6-4.
This will be the fourth singles final of Baez's career, though his first on home soil.
"It means a lot, but [it brings] confidence," said Baez.
"I have my people here, my friends, my family, everything, so that is a big motivation for me."
While Coria and Baez have just five previous final appearances between them, John Isner advanced to a 31st Tour-level showdown of his career as he beat fellow American J.J. Wolff at the Dallas Open.
Playing in his home city, 37-year-old Isner came from behind to prevail 3-6 7-5 7-6 (7-4).
Isner offered up eight break points, but saved seven of them to frustrate Wolff.
"I saved a lot of break points with unreturnable serves," Isner said. "Without that I would have been dusted off the court 6-3, 6-4. I'm of course very fortunate to have that weapon in my pocket, and I needed every bit of it today.
"It was an absolute battle, so I'm pretty tired. But I'm absolutely ecstatic to be in the final tomorrow here in Dallas."
Asked how he was faring up after his long tussle with Wolff, Isner quipped: "Truthfully, it feels terrible right now. I'm 38 in April. It's not getting any easier. I started off a little slow, a little sluggish, but in the third set I actually felt the best I felt the whole match.
"I had a lot of adrenaline there at the end and I was able to hold my nerve and win. Right now the name of the game is recovery."
Isner will be the favourite in the final, after top seed Fritz surrendered a lead in a 6-7 (3-7) 7-5 6-4 loss to Wu Yibing.
It was a tremendous week in Acapulco for the Australian, having eliminated world number 10 Holger Rune in the semi-final en route to his seventh title overall, with the first six all at the ATP 250 level.
Against Paul, De Minaur blew a pair of break points in the opening set, and then gave up the break in the very next game, allowing the American to serve things out safely to take the first frame.
But mistakes started to creep into Paul's game the longer the match went. After landing 75 per cent of his first serves fair in the opener and avoiding any double-faults, Paul's first serve percentage dropped to 46 in the second, and he committed a pair of doubles.
He committed another two double-faults in the decider to hand De Minaur the early break, and his play from the baseline also deteriorated, hitting just six winners to go with 14 unforced errors.
Known for his resilience, De Minaur had to save five break points to hold serve in the opening game of the third set, but he held his nerve, and churned out five consecutive games as Paul ran out of gas.
The 500 ranking points will see the Aussie climb to 18th in the world, with his career-best mark of 15th now within reach.
Meanwhile, the fairytale continued for Nicolas Jarry at the Chile Open, with the Santiago-born talent electrifying his home crowd with a 1-6 7-6 (7-4) 6-1 semi-final victory over Jaume Munar.
Jarry will get a chance for the second ATP title of his career, and the first since 2019, when he meets Tomas Martin Etcheverry in the final.
Etcheverry emerged victorious 7-5 6-3 in an all-Argentine showdown against third seed Sebastian Baez, earning his first final appearance at this level.
It was a tremendous week in Acapulco for the Australian, having eliminated world number 10 Holger Rune in the semi-final en route to his seventh title overall, with the first six all at the ATP 250 level.
Against Paul, De Minaur blew a pair of break points in the opening set, and then gave up the break in the very next game, allowing the American to serve things out safely to take the first frame.
But mistakes started to creep into Paul's game the longer the match went. After landing 75 per cent of his first serves fair in the opener and avoiding any double-faults, Paul's first serve percentage dropped to 46 in the second, and he committed a pair of doubles.
He committed another two double-faults in the decider to hand De Minaur the early break, and his play from the baseline also deteriorated, hitting just six winners to go with 14 unforced errors.
Known for his resilience, De Minaur had to save five break points to hold serve in the opening game of the third set, but he held his nerve, and churned out five consecutive games as Paul ran out of gas.
The 500 ranking points will see the Aussie climb to 18th in the world, with his career-best mark of 15th now within reach.
Meanwhile, the fairytale continued for Nicolas Jarry at the Chile Open, with the Santiago-born talent electrifying his home crowd with a 1-6 7-6 (7-4) 6-1 semi-final victory over Jaume Munar.
Jarry will get a chance for the second ATP title of his career, and the first since 2019, when he meets Tomas Martin Etcheverry in the final.
Etcheverry emerged victorious 7-5 6-3 in an all-Argentine showdown against third seed Sebastian Baez, earning his first final appearance at this level.
Baez was on the verge of a huge win on Court Philippe-Chatrier, but Zverev roared back to win 2-6 4-6 6-1 6-2 7-5 and move into the third round.
It was the third time the German had come from two sets down to secure a victory, having done so at the 2019 US Open semi-finals and at the 2021 French Open.
Zverev, who saved match point, claims he was thinking about being on the beach when he was on the ropes at Roland Garros.
"I couldn't have played any worse [at the start], I just tried to find a rhythm and did that. I'm happy still being in the tournament right now," he said.
"I was planning my holiday in Monaco, where I was going to go and who I was going to with and that relaxed me, thinking about the beach.
"You just have to find a way. You talk about mental strength and the greats, like Rafa [Nadal], Roger [Federer] and Novak [Djokovic], they always find a way.
"I will never be at their level, but I'm trying to get closer to them."
Zverev spoke to Baez at the net following his victory, and asked what he said to the 21-year-old Argentine, he replied: "I told Sebastian this is the worst you will ever feel on a tennis court, right now at this moment.
"I know how he feels as I lost the US Open final from being two sets up and was two points away.
"Then the next season I won an Olympic Games gold medal, so you always get better. He is an unbelievably great kid and he will do a lot of unbelievable things in this sport."
Zverev will next face Brandon Nakashima, who has reached the third round in a grand slam for the first time on his debut in Paris.
The German will hope to sure up his game for that match, given he made 46 unforced errors against Baez - just one fewer than his opponent.
Fritz, the third seed, faced sixth seed and world number 15 Frances Tiafoe, and did not allow a single break of serve en route to the 96-minute victory.
He will now face compatriot Tommy Paul in an all-American semi-final after the world number 23 prevailed 6-2 6-2 against Mackenzie McDonald.
The win was Paul's 10th from his past 12 matches, with one of those two losses coming against Novak Djokovic.
Australia's Alex De Minaur is through to the other semi-final after making light work of Japan's Taro Daniel 6-2 6-2 in a surprisingly one-sided contest, considering Daniel was coming off a victory over world number four Casper Ruud.
De Minaur will face Holger Rune after the 19-year-old capitalised on Matteo Berrettini not being at 100 per cent, jumping out to a perfect 6-0 1-0 start before the Italian retired hurt.
Meanwhile, Chile Open second seed Francisco Cerundolo missed out on a potential chance to face his younger brother after going down 6-3 3-6 6-3 against Tomas Martin Etcheverry.
He was one win away from doing his part to set up a quarter-final showdown with Juan Manuel Cerundolo, but the 21-year-old Argentine also did not hold up his end of the bargain, falling 6-2 2-6 7-6 (7-2) to Serbia's Dusan Lajovic.
Laslo Djere ensured it would be a good day for the Serbians with a 7-5 7-5 handling of Italy's Riccardo Bonadio, and he will face third seed Sebastian Baez in the quarter-final after he eliminated hometown hero Cristian Garin 6-4 6-3.
Second seed Medvedev cruised past Italian qualifier Andrea Vavassori 6-4 6-3, teeing up a meeting with Alexander Shevchenko, who overcame Jiri Lehecka in straight sets.
Tsitsipas was made to work by Dominic Thiem, but the fourth seed battling from a set down to win 3-6 6-1 7-6 (7-5).
World number 40 Dusan Lajovic provided the shock of the day by defeating seventh seed Auger-Aliassime 6-2 3-6 7-6 (7-5).
Denis Shapovalov, the 21st seed, was another surprise second-round loser, falling 6-7 (4-7) 6-4 7-6 (7-1) to China's Zhang Zhizhen.
Taylor Fritz avoided adding to the list of notable early eliminations in the Spanish capital, the eighth seed battling to a 7-6 (13-11) 6-4 victory over Christopher O'Connell.
Fritz's fellow American Frances Tiafoe progressed with a 6-3 7-6 (7-5) triumph over Argentina's Tomas Martin Etcheverry, while 14th seed Tommy Paul crashed out after a 6-3 7-6 (7-3) defeat to Roman Safiullin.
Seeds Alex de Minaur and Sebastian Baez also navigated their way through to the third round, defeating Marco Cecchinato and Marcos Giron respectively, as did Cameron Norrie at the expense of Yosuke Watanuki.
World number one Medvedev fought back from a set down to defeat Aslan Karatsev 3-6 6-4 6-2 and advance to a quarter-final against fifth seed Roberto Bautista Agut, who was granted a walkover after Nick Kyrgios pulled out with an abdominal issue.
The Russian got just 48 per cent of his first serves in during a blustery opening set before improving to 68 per cent in the second and controlling the decider as Karatsev struggled with injury.
"It was tough to play [in] rhythm. It felt like many points were just whoever managed to put the ball in the court was going to win the point," Medvedev said of the tricky conditions.
"It was not easy but I'm happy to win because that's the most important [thing].
"Last year was amazing. I played great tennis. Hopefully I can do the same this year. I like it here in Mallorca, so hopefully I can stay as long as possible in the tournament."
Alongside Medvedev and Bautista Agut, Stefanos Tsitsipas is the only other seed left in the draw after he overcame Ilya Ivashka 6-4 6-4.
Denis Shapovalov was a 6-4 6-1 loser against Benjamin Bonzi, Pablo Carreno Busta went down 6-3 6-4 to Antoine Bellier and Sebastian Baez's meeting with Daniel Altmaier ended in a 6-2 2-6 6-4 defeat for the Argentine.
At the Eastbourne International, second seed Sinner suffered a 6-3 3-6 6-3 loss to Tommy Paul as he made his return from a knee injury sustained at the French Open.
World number 13 Sinner remains without a grass-court win in his ATP Tour career, while Paul will next face defending champion Alex de Minaur, who overcame Lorenzo Sonego 7-6 (7-3) 6-2 in a repeat of last year's final.
Jack Draper defeated fourth seed Diego Schwartzman 7-5 7-6 (7-3) to advance to the quarter-finals and Cameron Norrie cruised past Brandon Nakashima in straight sets.
There were also wins for Maxime Cressy, Alexander Bublik and Taylor Fritz.
World number two Medvedev was making his first appearance since March after undergoing a hernia operation and fell to a 6-2 7-6 (7-5) defeat.
The Russian's rustiness was clear in the last-16 tussle as he racked up seven double faults and struggled to make inroads on Gasquet's second serve, with the Frenchman winning 61 per cent of points behind it.
It was the first time Gasquet overcame an opponent ranked in the top two since beating Roger Federer at the 2005 Monte Carlo Masters.
Next up for Gasquet will be Kamil Majchrzak, who beat Marco Cecchinato 6-2 6-3.
At the last-32 stage, Fabio Fognini went down 6-4 6-3 to Thanasi Kokkinakis and Albert Ramos-Vinolas succumbed to a 7-6 (7-5) 6-4 loss against Christopher O'Connell.
Johan Nikles, Nikoloz Basilashvili and Joao Sousa also advanced to the second round.
Top seed Cameron Norrie cruised into the quarter-finals of the Lyon Open by beating Francisco Cerundolo 6-4 6-4.
The Briton will face another Argentinian next in the form of Sebastian Baez, who came from a set down to beat Oscar Otte 5-7 6-4 6-2.
Alex De Minaur also had to rally for a 1-6 6-3 6-2 win against Ugo Humbert, with Yosuke Watanuki awaiting in the last eight after the world number 263 beat Soonwoo Kwon 6-3 6-4.
Bublik and Murray have now beaten each other two times apiece this year after the third seed won 7-5 6-4 in Newport.
The Kazakh overpowered the three-time grand slam champion to move into the last four, winning 80 per cent of his first-serve points and breaking three times.
Murray hit back straight after being broken at the start of the second set, but the former world one trailed 4-3 after failing to hold for a third time and Bublik did not give him another look-in.
Bublik will do battle with Jason Kubler for a place in the final after he defeated fellow Australian James Duckworth 7-5 7-6 (7-3).
Sebastian Baez ended Thiem's encouraging run to the quarter-finals with a 6-2 6-7 (5-7) 6-4 win in Bastad.
Thiem, who has endured an injury nightmare, won his first match 14 months by beating Emil Ruusuvuori in the first round and followed that up by getting the better of Roberto Bautista Agut, but the former US Open champion will go no further.
Argentinian Baez will now come up against Andrey Rublev after the second seed from Russia saw off Laslo Djere 7-5 6-4.
Pablo Carreno Busta blew Diego Schwartzman away in a 6-1 6-0 thrashing, while Francisco Cerundolo got past Aslan Karatsev in straight sets.
Murray needed less than an hour to record a 6-2 6-0 triumph over the big-serving American, setting up a last-16 meeting with Australia's Max Purcell.
Three-time grand slam champion Murray hobbled out of his last meeting with Querrey at the Wimbledon quarter-finals in 2017, a defeat which marked the start of his injury woes.
But he produced a polished display on the grass to wrap up his eighth career win over the American on Tuesday.
Elsewhere in Rhode Island, eighth seed James Duckworth battled to a 6-2 4-6 6-2 win over Liam Broady, and seventh seed Jiri Vesely raced to a 6-4 6-2 triumph against Spain's Feliciano Lopez.
Meanwhile, Thiem ended a 426-day wait for a Tour-level win by overcoming Finland's Emil Ruusuvuori 3-6 6-1 7-6 (7-5) at the Swedish Open.
The Austrian, who has won 17 career titles, halted a run of 10 consecutive losses on the ATP Tour with his first triumph since he beat Marton Fucsovics at the last-32 stage of the Internazionali d'Italia in May 2021.
The 28-year-old expressed his delight at ending his drought in the aftermath, saying: "It's a long time. My last victory was in Rome in 2021, it feels like a different world somehow.
"Many, many things happened. It was tough, but it was also a very good experience I think, for life in general. I'm so happy that I got this first victory here today."
Thiem will face fourth seed Roberto Bautista Agut in the last 16, while Sebastien Baez will take on Alejandro Davidovich Fokina after the former beat Fabio Fognini in straight sets.
The round of 32 did see two shock exits, however, with seventh seed Holger Rune succumbing to a 6-3 6-3 defeat against Switzerland's Marc-Andrea Huesler, and Nikoloz Basilashvili being forced to retire at one set down against Hugo Gaston.
Also, Francisco Cerundolo beat Pedro Sousa to set up an enticing clash with top seed Casper Ruud.
The world number four's bid for an 11th title in Rome got off to a strong start on Wednesday as he saw off big-serving Isner 6-3 6-1 in a time of 76 minutes.
Isner twice missed the chance to break Nadal in the seventh game of the opening set and the Spaniard took control from that point on in the second-round match.
Nadal, who has won this tournament in three of the past four years, identified that hold of serve as a key point in the contest.
"The beginning of the match was not good for me," he said in his on-court interview. "He had some chances on the return and had two break points.
"He had two not difficult balls so I was in his hands at that moment. I was lucky that he missed those shots and then I was able to break.
"Then the match changed, of course. With the first set on the board, and having the break in the first game of the second set, everything changed."
Nadal will now face Shapovalov in a repeat of last year's last-16 encounter, which the record 21-time grand slam winner edged in three sets.
He recovered from a set down and saved two match points before beating the Canadian 3-6 6-4 7-6 (7-3) en route to lifting the title in the Italian capital.
And Nadal, who was beaten by Carlos Alcaraz on clay in last week's Madrid Open quarter-final, is not expecting an easy task this time around.
"Last year was a joke, the match that I saved here against him," said Nadal of his next opponent. "I was super lucky. I know how dangerous he is, I need to play well.
"I need to play better than today, but after a while without being on court it is another victory and I have the chance again to play against one of the best players in the world.
"I need to build things again after a tough stoppage and that's what I am trying now. I just need to stay with the right attitude, and let's see if I am able to make that happen."
Alexander Zverev also booked his place in the last 16 on Wednesday thanks to a 7-6 (8-6) 6-3 victory over Sebastian Baez.
Last week's Madrid Open runner-up was given a tough time of things by in-form Baez, but ultimately came through unscathed to stay on course for more silverware.
Paul edged the third seed 6-3 6-7 (2-7) 7-6 (7-2) in three hours and 29 minutes in their semi-final clash in Acapulco.
World number 23 Paul actually generated a match point late in the second set but spurned his initial chance, then waiting another two hours before winning in the third-set tie-break.
Paul let match point slip at 5-4 in the second set and had to rally back from 3-1 down in the third, but triumphed on his fourth match point.
"I couldn't be happier," Paul said. "The goal for this year was to get the ranking up and get more trophies. I only have one trophy on Tour between singles and doubles.
"You don't get trophies unless your in the final, and hopefully I can play another good match tomorrow and get the winner's trophy."
The 2023 Australian Open semi-finalist will take on Alex de Minaur in Saturday's decider, after he defeated Holger Rune 3-6 7-5 6-2 in two hours and 50 minutes.
In the Chile Open, local Nicolas Jarry progressed into the semi-finals with a 3-6 6-3 6-4 win over German qualifier Yannick Hanfmann. Jarry will face Spaniard Jaume Munar after he won 6-3 3-6 6-2 over Thiago Monteiro.
Third seed Sebastian Baez got past Laslo Djere 7-6 (7-4) 6-4, setting up a semi-final date with Tomas Martin Etcheverry after he won 6-1 6-2 over Dusan Lajovic.
Peniston beat world number five Casper Ruud as he reached the quarter-finals at the Queen's Club Championships last week, and followed that up by recovering from a set down against Rune to reach Eastbourne's last 16 in impressive fashion.
After wrapping up a 4-6 7-6 (7-5) 6-1 win, the 26-year-old told the home crowd: "I'm very happy with that. A tough start but I managed to fight, thanks to you guys.
"Since Queen's it has been madness. A couple of weeks ago was a lot different and things have changed, but I'm loving it."
Rune, who was twice two points from victory in an enthralling contest, was jeered by spectators after hitting a ball out of court and kicking his towel bin after being broken in the third set.
Peniston will face Pedro Martinez in the next round after he benefited from fellow Spaniard Alejandro Davidovich Fokina being forced to retire at one set apiece, while Ugo Humbert fell to a 6-7 (2-7) 6-3 6-4 reverse against Brazil's Thiago Monteiro.
Lorenzo Sonego posted a 4-6 7-6 (7-5) 7-6 (7-1) win over James Duckworth, while Tommy Paul recovered from a set down to beat Francisco Cerundolo and home favourite Dan Evans overcame Adrian Mannarino 6-4 6-3.
The seeds in action at the Mallorca Open endured mixed fortunes as Sebastian Baez cruised past Jordan Thompson in straight sets, but Botic van de Zandschulp was beaten by Marcos Giron.
The Dutchman succumbed to a 6-7 (6-8) 6-4 7-6 (7-2) defeat, while Germany's Daniel Altmaier beat Dusan Lajovic 7-5 7-6 (7-2).
Nick Kyrgios set up an enticing last-16 meeting with fifth seed Roberto Bautista Agut by knocking out Serbia's Laslo Djere in a marathon three-set contest, recovering to win 5-7 7-6 (7-1) 7-6 (7-1).
