Rafael Nadal has withdrawn from the Miami Open as he bids to recover full fitness in time for the European clay season.

The 20-time grand slam singles champion has not played since losing to Stefanos Tsitsipas in the quarter-finals of the Australian Open in February.

Nadal pulled out of the Rotterdam Open and turned down a wildcard for the Dubai Tennis Championships due to a persistent back problem.

The world number three, who has never won the title in Miami, wants to prioritise his recovery ahead of the beginning of the clay-court swing in April.

Writing on Twitter on Tuesday, he said: "Sad to announce that I won't be playing in Miami, a city that I love.

"I need to fully recover and get ready for the clay-court season in Europe. Special message to my fans in the US and in particular to the great Spanish-speaking community FL who always give me a great support!"

Nadal follows long-time rival Roger Federer in withdrawing from the tournament, the Swiss great choosing to focus on training after only returning to the Tour from a 14-month absence at the Qatar Open.

Federer is the reigning champion in Miami, having beaten 2018 winner John Isner in the final two years ago. The 2020 tournament was cancelled due to coronavirus concerns.

Alexander Zverev cruised into the second round of the Mexican Open as debutant Sebastian Korda enjoyed a memorable debut in Acapulco.

German star and second seed Zverev accounted for teenager Carlos Alcaraz, the 2019 runner-up winning the opening-round clash 6-3 6-1 on Monday.

Alcaraz – in his first showdown against a top-10 player – broke for a 2-0 lead and while he continued to go toe-to-toe with Zverev through six games, the 17-year-old was unable to maintain his charge.

Zverev broke for a 4-3 lead and the 2020 US Open finalist did not look back, winning nine of the last 10 games to advance in 84 minutes.

"He started off playing extremely well, he didn't miss a lot of balls. Then I felt more comfortable on court, this is the first round," Zverev said.

"It's not always easy to play a first round, especially against a player like this, who is very young, who is very motivated and who wants to compete. I'm actually quite happy with how the match went."

Next up for Zverev – who reached the Australian Open quarter-finals in February – is Serbia's Laslo Djere.

Djere took down Steve Johnson 6-2 6-3 for a spot in the last 16.

Meanwhile, Korda capped his Acapulco bow with a shock 7-5 6-2 win against former world number three Marin Cilic.

Korda claimed his first ATP 500-level victory having saved 10 of the 11 break points he faced in the opening set against the 2014 US Open champion.

Canadian sensation and seventh seed Felix Auger-Aliassime awaits after the 20-year-old converted his sixth match point to see off Tennys Sandgren 6-3 7-6 (10-8).

Elsewhere, John Isner and Dominik Koepfer also advanced.

Nao Hibino was a shock first-round casualty at the Monterrey Open, while fellow seed Ann Li advanced.

Seeded ninth for the WTA International tournament, Japan's Hibino was upstaged 3-6 6-2 6-3 by Jasmine Paolini on Monday.

American eighth seed Li, however, had no such trouble in her 6-3 7-5 victory over Arantxa Rus on the outdoor hard courts.

Coco Vandeweghe – the 2017 Australian Open semi-finalist – suffered another early exit in Mexico.

After being ousted by Mihaela Buzarnescu in the opening round in Guadalajara last week, former world number nine Vandeweghe was eliminated 6-3 6-2 by Canadian teenager Leylah Fernandez.

Fernandez will face either top seed Sloane Stephens or lucky loser Kristina Kucova in the second round.

Anna Karolina Schmiedlova, Nina Stojanovic, Viktoria Kuzmova, Lauren Davis and Tamara Zidansek also progressed from the opening round.

Former world number one Andy Murray will compete at the Miami Open for the first time since 2016 after being granted a wildcard.

Murray has not played on the ATP Tour since last month's Rotterdam Open, where the three-time major champion lost to Andrey Rublev in the round of 16.

But Murray – who won the ATP 1000 event in 2009 and 2013 – is set to end his Miami absence, having undergone hip surgeries in 2018 and 2019.

"It's a city I love, and I've spent a lot of time here over the last 15 years, I feel comfortable," the 33-year-old, who sat out the Australian Open after testing positive for coronavirus, told PEOPLE Magazine.

"But over the next few months, I want to play matches — especially against the top players — work on my game and climb the rankings. I want to get back playing a sport I love."

Murray added: "The last few years has been really hard. After the operation, there were no guarantees I would play again, but I've been working very hard on my conditioning and over the last few months I've felt the best I have for years. 

"I'll need to be mindful of my schedule moving forward but I'm excited to be back competing — with a metal hip."

"But every match feels like progress and I'm learning from each one," he continued.

The Miami Open will get underway at Hard Rock Stadium on March 24 after the tournament was cancelled last year amid the COVID-19 pandemic.

"It is exciting to see Andy back in Miami," Miami Open Tournament Director James Blake said.

"As someone who has had to battle back from injuy during his career, I understand and respect all the hard work Andy has put in to get back on tour."

Alex de Minaur's tough run of form continued as he let a set lead slip to lose to Jeremy Chardy at the Dubai Tennis Championships on Monday.

De Minaur, the ninth seed in Dubai, won his first tournament of 2021 in Antalya in January.

However, the Australian's results since then have rapidly declined and his latest loss - 2-6 6-3 6-4 to Chardy - means he is 3-5 since his title in Turkey.

De Minaur seized his first two break points against Chardy, yet the next four came and went while his opponent proved clinical, taking his only two opportunities and snatching victory.

The Frenchman, who reached the semi-finals in Antalya and again at an ATP 250 event in Melbourne prior to the Australian Open, said: "I've played good since the beginning of the year.

"It is always easier to play when you are confident. If you play a bad set, it is never finished. I stayed focused and tried to find a solution."

It was not a successful start to the week for De Minaur's compatriots either, as John Millman was among three other Aussies to crash out.

Christopher O'Connell missed the chance to set up a meeting with Dominic Thiem as Lloyd Harris advanced, and qualifier Emil Ruusuvuori saw off Jordan Thompson ahead of facing Andrey Rublev.

Marton Fucsovics was back in action after handing a walkover to Rublev, the same man who had previously beaten him to the Rotterdam Open title, in Qatar last week.

He defeated Vasek Pospisil in three sets, while there was a milestone win for Richard Gasquet, another man unable to line up against Rublev in Doha.

A 6-4 6-2 win over Marco Cecchinato was his 550th on the ATP Tour, making him only the sixth active player to that mark after the 'big four' of Roger Federer (1,243), Rafael Nadal (1,008), Novak Djokovic (943) and Andy Murray (677) and Spain's Fernando Verdasco (552).

"I am feeling great here," Gasquet said. "I know this court well. I played well last year. It is a fast court. I like to play on it.

"It is important to serve well and it was a great match. I started well, feeling confident and winning the first set, and then I played better in the second set."

Jelena Ostapenko wasted little time in her opening match at the St Petersburg Ladies Trophy, while there were also wins for Aliaksandra Sasnovich and Vera Zvonareva in Monday's action. 

Ostapenko needed less than an hour to get past Paula Badosa, who caused an upset when the pair met at last year's delayed French Open. 

There was to be no Roland Garros repeat for Badosa, though, as she was swept aside 6-2 6-2.  

The sixth-seeded Ostapenko started her campaign impressively in Russia, producing 26 winners and just eight unforced errors. Her serve was also in good order, never giving her opponent a chance of a break. 

Sasnovich had to work a little harder, rallying from a set down to see off Ana Bogdan 2-6 6-2 6-1. Her reward is a clash with third seed Fiona Ferro, who received a bye through to the second round.

Zvonareva, meanwhile, progressed in straight sets against Arina Rodionova, the Russian dropping just four games during a contest that lasted one hour and 22 minutes.  

Victory was sealed at the second opportunity, a sliced backhand into the net by her opponent sending Zvonareva through to the last 32. 

Cristian Garin prevailed in his hometown, crowned Chile Open champion with a three-set victory over Facundo Bagnis.

Garin, who had not won a match in 2021 before arriving in Santiago, claimed his first ATP Tour trophy on home soil thanks to Sunday's 6-4 6-7 (3-7) 7-5 triumph.

The top seed and 24-year-old only dropped one set throughout the ATP 250 tournament as he became the first Chilean player to win a home event since Fernando Gonzalez in 2009.

Bagnis was contesting his first final aged 31 and he was unable to see it through against Garin, who celebrated his fifth ATP title – all of them on clay.

Daniil Medvedev claimed the 10th ATP Tour title of his career with a 6-4 6-7 (4-7) 6-4 win over Pierre-Hugues Herbert at the Open 13 Provence in Marseille.

Medvedev will move up to number two in the world in Monday's latest ranking, making him the first player outside of the big four of Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray to occupy one of the top two positions since Leyton Hewitt in 2005.

The Russian celebrated this achievement with a dogged display to down Herbert in two hours and 11 minutes, saving four of the five break points he faced.

A finalist at the Australian Open, Medvedev is now 14-2 in 2021, with the Open 13 title his sixth on indoor hard courts.

Herbert's strategy of frequently visiting the net was initially picked apart by Medvedev, who only needed one set point in the opener as he threaded a backhand winner expertly down the line.

But the Frenchman applied the pressure in set two, passing up three break points early on before impressing from the baseline to reel off five straight points and claim the breaker from 2-4 behind.

The decider was a tense affair but Herbert's errors at the net came back to undermine his efforts decisively when he served to stay in the match at 5-4.

The 29-year-old has now lost all four of his ATP Finals, while Medvedev again proved himself to be a high-quality operator on such occasions.

Top seed and local hope Cristian Garin progressed to Sunday's Chile Open final after defeating Daniel Elahi Galan in straight sets in their semi-final.

The Chilean world number 22 triumphed over Colombian Galan 6-4 6-3 and will play 118th-ranked Facundo Bagnis in Sunday's decider in Santiago.

Garin sent down eight aces and was dominant on his first serve against Galan.

Santiago native Garin, 24, has never won an ATP Tour title on home soil, while no Chilean has won the event since Fernando Gonzalez in 2009.

"I'm so, so happy to be in the final," Garin said in his post-game on-court interview. "The first day that I arrived I wasn't playing well and it was my second tournament in months, so for me to be in the final is so special, and even more here in Chile."

Argentinian Bagnis defeated higher-ranked countryman Federico Delbonis 7-5 6-3 to secure his place in a maiden Tour final.

Cristian Garin continued his quest for Chile Open glory as another upset in the other half of the draw paired two Argentinians in the semi-finals.

Top seed Garin is aiming to win an ATP Tour event on home soil for the first time in Santiago.

The 24-year-old was made to work by Peruvian qualifier Juan Pablo Varillas in the last eight on Friday, but he prevailed 6-4 6-4.

Garin was broken first in either set yet responded instantly on each occasion.

"I would love to be able to do something important in this tournament," the Chilean said. "It is special and I hope I can continue to win.

"I am playing better, in a semi-final and I am excited to do better, but I prefer to go step by step, game by game."

Daniel Elahi Galan is up next, while the highest remaining seed besides Garin is Argentina's Federico Delbonis, the number eight.

That is because Facundo Bagnis set up a meeting with his compatriot by defeating fourth seed Laslo Djere.

Bagnis, who had already claimed the scalp of fifth seed Frances Tiafoe, dropped the first set but recovered to advance 4-6 6-3 6-3 at the ATP 250 tournament.

Stefanos Tsitsipas saw his hopes of a hat-trick of titles at the Open 13 Provence ended by a shock quarter-final defeat on Friday.

The second seed was upset by French world number 93 Pierre-Hugues Herbert, as the doubles expert scored a 6-7 (6-8) 6-4 6-2 win.

Herbert had won only one singles match on tour in 2021 before this week, but Kei Nishikori and Cameron Norrie fell to the 29-year-old in the early rounds before he stunned world number five Tsitsipas.

It was a first career win in singles over a player ranked in the world's top five for Herbert, and he said: "It has been an incredible week for me so far, especially this match."

Quoted on the ATP website, Herbert added: "I knew I was going to have to play an amazing match to have a chance to win and I managed to do that. I am really happy about the way I played. I am so happy to be in the semi-finals here."

A French finalist is guaranteed as Herbert will face compatriot Ugo Humbert in the semi-finals on Saturday.

Humbert beat another Frenchman, world number 138 Arthur Rinderknech, in a tight contest, saving a match point and coming through 4-6 7-5 7-6 (7-4) in two hours and 36 minutes.

Russian top seed Daniil Medvedev chased off the threat of Jannik Sinner at this indoor event for the second year running, securing a 6-2 6-4 success against the Italian teenager.

Their only two career meetings have come in Marseille, and Medvedev bossed this encounter, taking three of his five break chances and holding serve throughout.

He will face Australian Matthew Ebden in the final four after the world number 287 earned an eye-catching 4-6 6-4 6-2 win over Russian third seed Karen Khachanov, who was champion in 2018 in Marseille.

At the Qatar Open, Nikoloz Basilashvili backed up his three-set win over Roger Federer by reaching the final of the tournament.

The Georgian scored a 7-6 (7-3) 6-1 semi-final victory over American Taylor Fritz in a clash of two unseeded players.

Basilashvili will tackle Spain's Roberto Bautista Agut for the title on Saturday after the fifth seed ousted Russian third seed Andrey Rublev.

A 6-3 6-3 win for Bautista Agut nudged the man from Castellon de la Plana into a 3-2 career head-to-head lead over his Muscovite opponent.

Garbine Muguruza reached the final of the Dubai Tennis Championships after a gruelling victory over Elise Mertens on Friday.

The Spaniard saw six match points come and go in a battle lasting two hours and seven minutes before eventually closing out a 6-4 7-6 (7-5) win.

Having reached the final in Doha last week, where she lost to Petra Kvitova, Muguruza is the fifth player this century to reach back-to-back finals in the Middle East double, after Martina Hingis, Justine Henin, Caroline Wozniacki and Svetlana Kuznetsova.

The two-time major winner has now reached three finals in her past four tournaments and has won 17 matches in 2021.

Despite being ahead for much of the match, Muguruza was nonetheless pushed hard by Mertens, who fought back to beat Jessica Pegula in the quarter-finals after facing three match points.

She led by a set and 5-3 but Mertens continued to come up clutch at key points until Muguruza at last completed the job with a smash in the tie-break.

"You have to be all the time concentrated, otherwise she will come back," she said. "I didn't lose the focus even though I couldn't close it [at first] – I was just looking forward to the next opportunity.

"I didn't think I played bad on the match points. They were just tough points that didn't come to my side. She was very good in defence and on those points, I felt she brought her magic. But I was like, 'Okay, I'm playing well, sooner or later I will convert the match point'. I didn't lose the concentration or get too irritated."

Muguruza will face Barbora Krejcikova in the final, the Czech defeating Jil Teichmann 7-5 6-2.

Krejcikova saved 10 of 11 break points as she reached just the second Tour final of her singles career and has yet to drop a set at this tournament.

The world number 63 is the lowest-ranked singles finalist in history in Dubai, with that previous record held by Virginie Razzano, who was ranked 58 in the world when she lost to Venus Williams in 2009.

Top seed Cristian Garin will fly the flag for Chile in the quarter-finals of the Chile Open after beating compatriot Alejandro Tabilo in the second round.

The only two remaining home hopes in Santiago went head-to-head on Thursday and it was world number 22 Garin who came out on top 6-2 6-2.

Garin, a four-time ATP Tour winner, was forced to retire from the tournament in the last eight last year but will look to reach the semi-finals for the first time when he takes on Peruvian qualifier Juan Pablo Varillas.

The 24-year-old Garin is one of only three seeds remaining in the competition after Varillas' upset win over Federico Coria in straight sets and Daniel Elahi Galan's defeat of Pablo Andujar.

Garin cannot now play another seeded player until the final.

Elise Mertens came from behind to clinch a semi-final spot at the Dubai Tennis Championships but Coco Gauff bowed out on Thursday.

Mertens said she "just didn't want to let go" after coming back from the brink to end Jessica Pegula's fine run with a 5-7 7-5 6-0 victory.

The Belgian looked to be heading out when she faced a 5-2 deficit in the second set, yet saved three match points to force a decider.

"I kept on fighting and that was the spirit today," said world number 18 Mertens.

Former world number one Muguruza is Mertens' semi-final opponent, the Spaniard having come from a set down to beat third seed Aryna Sabalenka 3-6 6-3 6-2.

Muguruza lost out to Petra Kvitova in the final of the Qatar Open last week, but looks on top form as she closes in on another championship match.

Sabalenka fell foul of Muguruza in Doha, and the Belarusian was unable to gain revenge as the ninth seed earned a 16th win of the season.

There was to be no place in the last four for 16-year-old Gauff, who came up short against world number 54 Jil Teichmann.

Gauff, who defeated Teichmann twice in Australia in February, was broken to go 5-3 down in the first set and could not respond.

A second break in Teichmann's favour put Gauff on the back foot in the second, and the Swiss then saved three break points to nose into a 3-1 lead.

The contest was settled on Gauff's serve – Teichmann taking the match at the second time of asking to tee up a last-four clash with Barbora Krejcikova, who beat Anastasia Potapova 6-0 6-2 in a little over an hour.

Krejcikova was beaten in the doubles final last year, and has claimed her place in the singles semi-finals of a WTA 1000 event for the first time.

Roger Federer's return to the ATP Tour lasted just two matches at the Qatar Open as he was beaten in the last eight by the brilliant Nikoloz Basilashvili.