Tennys Sandgren

Sandgren is the world number 100 but has an unusually strong record against top-10 opponents, scoring wins over Stan Wawrinka, Dominic Thiem, Fabio Fognini and, earlier in this tournament, Matteo Berrettini.

The 28-year-old from Tennessee only made his grand slam main-draw debut in 2017 and is, by modern tennis standards, a late developer.

In 2014, he lost a Challenger Tour match to Britain's Marcus Willis, who famously chomped on a chocolate bar and sipped a cola drink rather than elect for snacks more usually associated with professional sport stars.

That match was highlighted, raking up bad memories for Sandgren, when Willis made a name for himself in 2016 at Wimbledon, the genial home player taking on Federer in a highly entertaining but one-sided second-round match on Centre Court.

Now, though, it is Sandgren's turn to tackle the 20-time grand slam winner, and their clash should be competitive.

"I wonder why he's not ranked higher, to be honest," Federer said of Sandgren. "Every time I see him play, I feel like he plays very well. He's got a lot of stuff in his game that [means] he's deserving of being higher.

"I'm looking forward to that match because I've seen him play a lot but never played him."

Sandgren repeated his 2019 Wimbledon win over Fognini to sink the Italian's hopes over four sets in Melbourne on Sunday, and Federer took the chance to watch, predicting "a tough one" next.

For his part, Federer overcame a sluggish start to see off Marton Fucsovics 4-6 6-1 6-2 6-2, with any effects of his late-night battle with John Millman in the third round seemingly shaken off.

Sandgren was asked why he has shown himself capable of doing well on the big occasion.

"Maybe because I haven't had that many," Sandgren said. "Maybe I haven't had that many looks or wasn't supposed to.

"Maybe I shouldn't be here. The fact that I am, I get kind of amped up. I want to perform. I want to do well. I don't want to take the time on the court for granted.

"Getting to play in a big stadium, getting to play in front of a lot of people, because I've played a lot of tennis in front of very few people, that seems to bring out the best tennis in me."

Sandgren's big shot is his serve, as Federer has observed.

The Swiss has taken down many a player with a booming serve in the past, yet he has also been struck by other areas of Sandgren's game, saying: "He can counter-punch but also likes to go on the attack."

Sandgren spoke of how he spent his early years in tennis "not sniffing these opportunities" and claimed: "There are better players than me that I played with in Futures and Challengers that have stopped playing because they just ran out of money or got injured.

"There's definitely a world where it didn't work out [for me]. Some of the margins were pretty small for me to have some of these opportunities. I definitely don't take it for granted."

He was also reminded of the Willis match, which took place on an indoor court in front of a spartan crowd.

"I did not feel great after that one. He downed an RC Cola and a Snickers and took me out," Sandgren recalled. "I had a few of those where it's like, 'What are you doing? Is this ever going to be worthwhile?'"

The American triumphed in four sets - three of which went to tie-breaks - to knock out the 12th seed and book a meeting with Federer, who dispatched Marton Fucsovics after a nervy start.

There were few signs of the jitters for Novak Djokovic against Diego Schwartzman, while Milos Raonic's relentless serving strength saw him power past 2018 finalist Marin Cilic.

Canadian Raonic said he felt "pretty damn good" after a straight-sets win that included 35 aces, although he admitted he will need even more to beat defending champion Djokovic next.

SANDGREN FIGHTS THROUGH FOGNINI FRUSTRATION

Sandgren traded winners and barbs with Fabio Fognini before prevailing 7-6 (7-5) 7-5 6-7 (2-7) 6-4 to seal his second Australian open quarter-final berth.

Tempers frayed across four entertaining sets on Melbourne Arena, with the American becoming upset at his opponent's stalling tactics.

Fognini, the 12th seed, argued with the umpire, took a lengthy bathroom break and asked for a medical timeout to treat blisters all before the third set, leading Sandgren frustrated.

"He gets his own rules because you're afraid to step on his toes," the world number 100 told the umpire after taking the opener.

Sandgren, who lost to Chung Hyeon in the last eight two years ago, regained his composure and went on to complete the upset in three hours and 27 minutes.

FEDERER FINDS FORM AFTER EARLY WOBBLE

Federer seemed to be feeling the effects of his epic five-set victory over John Millman as Fucsovics took an early lead on Rod Laver Arena.

However, the 38-year-old recovered in supreme style and seemed somewhere close to his best tennis at the end of a 4-6 6-1 6-2 6-2 victory.

As the full repertoire of shots from Federer began to paint the lines, Fucsovics had little response.

The 20-time major champion is now looking forward to a first meeting with Sandgren. "I have played a lot of tennis in my life, but never against Tennys," he said.

DJOKOVIC POWERS PAST SCHWARTZMAN

Djokovic produced another dominant display to dismantle Schwartzman 6-3 6-4 6-4 on Rod Laver Arena, where the world number two kept his title hopes alive.

While Schwartzman fought hard, it was another routine outing for Djokovic - who reached his 11th Australian Open quarter-final.

Djokovic was broken for the first time since the opening round but was never really in danger, hitting 38 winners and 31 unforced errors.

"Today was a good test because Diego was in form, he hasn't dropped a set in three rounds," the Serbian said afterwards.

"Obviously he can be a very dangerous opponent from the baseline if you give him time. I knew that. I stepped out on the court with a clear game plan what I need to do."

RAONIC TAKES DOWN CILIC

It rained aces as 32nd seed and former world number three Raonic beat former runner-up Cilic 6-4 6-3 7-5.

Raonic progressed to his fifth quarter-final in Melbourne after firing down 35 aces and winning all of his service games in two hours and 19 minutes.

His reward? A showdown with Serbian superstar Djokovic, who boasts a dominant 9-0 head-to-head record.

"I'm going to have to serve well clearly, and then I think I'm going to have to get my return at a high percentage, make him play a lot of those points, and then try to be efficient on my service games," Raonic said in his news conference.

"I think we play quite opposite from each other, and he's done a good job in the past neutralising my serve. So I have really got to focus on my things well and be the one dictating."

Federer – battling injury – incredibly saved seven match points before claiming a 6-3 2-6 2-6 7-6 (10-8) 6-3 victory on Rod Laver Arena on Tuesday.

Sandgren was somewhat tentative and Federer gave nothing away during those decisive moments, with the 20-time grand slam champion coming from 6-3 down in the tie-break in the fourth set.

The American, left tired after a battle lasting three hours and 31 minutes, gave credit to Federer.

"I just tried to keep playing it, playing the tennis portion of it," Sandgren told a news conference.

"Like I said, it just seemed like his level picked up when his back was right up against the wall.

"He just wouldn't give me anything. Credit to him, for sure."

Sandgren only had one match point on his own serve, while four came after Federer missed first serves.

The world number 100, who was playing his second grand slam quarter-final, felt the missed opportunities were not as bad as they looked

"One on my serve. Really not that many. If I had, like, six on my serve, I'd be really p***** off," a smiling Sandgren said.

"One on my serve, and I think I made the first serve, he gave it a good stick on the forehand, which is not surprising either, yeah."

The 20-time grand slam champion appeared set for a shock loss in Melbourne, battling a leg injury from the third set onwards on Rod Laver Arena.

Instead, he delivered a spectacular comeback, reaching the semi-finals with a 6-3 2-6 2-6 7-6 (10-8) 6-3 victory that was special even by his standards across three hours, 31 minutes.

Federer saved seven match points in the fourth set, including coming from 6-3 down in the tie-break, having needed a medical timeout.

The 38-year-old moved into his 46th grand slam semi-final and became the oldest man to get into the last four at the Australian Open since Ken Rosewall in 1977.

After squandering five early break point chances, Federer took his sixth when Sandgren sent a backhand long in the sixth game.

While Federer closed out the opener, a flurry of errors saw him give up a break and fall 3-0 behind to begin the second.

Federer committed 15 unforced errors in the second set – eight from the backhand side – as Sandgren levelled the match.

The Swiss great's struggles continued into the third, broken in the second game when he sent a tame forehand into the net.

Sandgren came from 0-40 down in the third game of the set, during which a frustrated Federer was given an audible obscenity warning before receiving treatment off the court.

Struggling physically, Federer tried to hang in there before giving up the set with a backhand into the net.

Mixing his game up, Federer fought hard against a seemingly undistracted Sandgren in the fourth set before saving three match points in the 10th game as the American faltered.

Sandgren put two match point opportunities into the net and sent another wide before saving a break point to take a 6-5 lead.

In an extraordinary tie-break, Federer came from 6-3 down and saved four more match points to force a decider as the Rod Laver Arena crowd erupted.

Federer had his right hamstring treated before the fifth set and he appeared far more mobile as he took control of the contest.

A break for 4-2 set him up and he had no trouble closing it out, an unreturnable serve wrapping up the amazing comeback.

STATISTICAL BREAKDOWN 
Roger Federer [3] bt Tennys Sandgren 6-3 2-6 2-6 7-6 (10-8) 6-3

WINNERS/UNFORCED ERRORS  
Federer – 44/56
Sandgren – 73/53

ACES/DOUBLE FAULTS  
Federer – 5/3
Sandgren – 27/5

BREAK POINTS WON  
Federer – 2/13
Sandgren – 4/14

FIRST SERVE PERCENTAGE  
Federer – 65
Sandgren – 65

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE  
Federer – 71/53
Sandgren – 79/45

TOTAL POINTS  
Federer – 160
Sandgren – 161

After winning the first set with little fuss, Federer began to struggle and lost the next two 6-2 to the American, requiring a medical timeout when 3-0 down in the third.

With his groin and leg causing Federer discomfort, he was on the brink of defeat in the fourth set, facing a total of seven match points.

But he showed remarkable resilience to fight back and level the contest, with a visibly frustrated Sandgren struggling to keep his emotions in check.

Federer closed out the match, taking the final set to clinch a 6-3 2-6 2-6 7-6 (10-8) 6-3 victory, but he claimed he did not deserve the victory given Sandgren outscored him in terms of aces, overall points and winners.

"You've got to get lucky sometimes, I'll tell you that," a jovial Federer said in his on-court interview. "In those seven match points you're not in control, it may not look that way.

"I don't know, I was just hoping that he wasn't going to smash the winner on that one point, and just keep the ball in play, and if he misses one or two, who knows what he's thinking about?

"Even that didn't really matter. I think he played his match, I got incredibly lucky and then as the match went on, I started to feel better again.

"All the pressure went away, and I started to play. Again, I got a little lucky with the breaks and served really well I think for most of the game, particularly at the end.

"I don't deserve this one, but I'm standing here and obviously very happy.

"I don't like calling the trainer, ever, because it's a sign of weakness and all that stuff, and I try not to show it. The best is when it's a groin [injury], so you go off court and no one knows what it is.

"I just said, 'I believe in miracles'. It could rain, there could be stuff [happening]. It [the injury] wasn't bad enough where I thought it was going to get worse, I was just stiff and tight – [I was thinking] 'let him finish me off in style', and he didn't do that, so I'm incredible lucky today, tonight… I don't even know what time it is."

The 20-time grand slam winner will face either Milos Raonic or defending champion Novak Djokovic in the semi-finals and, while the prospect of facing the latter when not 100 per cent fit is by no means kind, Federer is ready to embrace whatever happens after riding his luck.

"The draws are not getting easier, but I've got the rest of the day with nothing to do, the next day with nothing to do and then I'm playing at night. You do feel better in a couple of days and then you never know," he said.

"With these lucky escapes, you might play without any expectations anymore because you know you should already be skiing in Switzerland! I'm lucky to be here and might as well make the most of it."

Federer saved seven match points in a thrilling 6-3 2-6 2-6 7-6 (10-8) 6-3 victory over Sandgren in Melbourne on Tuesday.

The 20-time grand slam champion took a medical timeout during the third set and later revealed his groin was troubling him.

Federer, 38, hopes the worry is minor ahead of a semi-final against either Novak Djokovic or Milos Raonic on Thursday.

"I don't know if you can call it an injury. It's just pain and problems. I need to figure it out now," the Swiss great told a news conference.

"But as it's not like in 18 hours, like you got a third round to play, semi-finals, you have an extra day, adrenaline, there's a lot of things. Two good nights of sleep, doctors, physios.

"Hopefully we'll find out that it's actually nothing bad, that it was just the groin that went really tight from playing a lot, who knows what, from nerves.

"I don't know. I'm hopeful. We'll find out tonight, tomorrow. The next day we'll see how it goes."

Federer has already spent 12 hours and 38 minutes on court, only winning his first two matches in straight sets and being pushed to five twice.

But despite his worries, the six-time champion in Melbourne still believes in his chances of success at the year's first grand slam.

"I mean, look, if I can get through a match like this, through a match like [John] Millman [in the third round], yeah, you do believe," said Federer, who also had treatment on his right hamstring before the final set.

"I only believe it once it's over, I shake the hand of the opponent, that it's over, that it's fine.

"So, yeah, I do always believe until it's actually over, never before."

After saving seven match points, Federer overcame Tennys Sandgren 6-3 2-6 2-6 7-6 (10-8) 6-3 in an epic Australian Open quarter-final on Tuesday.

It was often scrappy and at times workmanlike, but the Swiss great delivered once more – albeit in a different way – on the grand slam stage.

Federer is a 20-time grand slam champion whose last major success came in 2018 and has two fellow all-time greats standing in his way over and over again on the biggest stage.

So, battling a leg injury which seemed to improve as the match went on, he needed three hours, 31 minutes to beat the American world number 100.

He hit 56 unforced errors and now has 208 for the tournament at an average of 41.6 per match. He had what looked like a soft draw and has turned it into 12 hours, 38 minutes of time on court, including two huge comebacks in five-setters.

It is the first time in his illustrious career that Federer has not faced a top-40 opponent on his way to a grand slam semi-final. Steve Johnson (75), Filip Krajinovic (41), John Millman (47), Marton Fucsovics (67) and Sandgren (100) should not have caused him as many problems as they have.

At 38 and with Novak Djokovic and Rafael Nadal, 32 and 33 years old respectively, continually standing in his way, Federer is going to have to deliver in ways other than winning grand slams.

On a slow court and with Djokovic likely awaiting in the semi-finals, his Australian Open chances seem slim even though he is into the last four. Wimbledon is still shaping as his best hope of another grand slam, yet he has thrilled more so than anyone else at the year's first major.

After his win over Millman, when he came from 8-4 down in the match tie-break, Federer said: "I think if I do play tennis it's because of winning titles, trying to win as many matches as possible, enjoy myself out on court but also being in epic matches like this.

"It doesn't always have to be finals, I guess. As long as the crowds are into it, you have a great battle with an opponent who you really admire and respect, it's a good feeling.

"I'm happy I had that match. I hope I would feel the same way also if I would have lost, to be honest."

Crowds are always behind Federer and again it proved on Tuesday at Rod Laver Arena and, if entertainment is the objective, he – and Sandgren – well and truly delivered.

It wasn't vintage Federer, but so what?

Federer banished the demons of last year's shock fourth-round exit by topping Marton Fucsovics in Melbourne on Sunday.

A 20-time grand slam winner and six-time champion at Melbourne Park, Swiss maestro Federer is eyeing his first major title since the 2018 Australian Open.

As Federer prepares for the last eight, we look at the 38-year-old's form.

Form and results

Like his five-setter with John Millman, Federer dropped the opening set against Fucsovics on Sunday. However, third seed Federer managed to avoid going the distance as he steamrolled his unheralded Hungarian opponent in two hours, 11 minutes. The veteran used 44 winners to vanquish Fucsovics under the Rod Laver Arena lights.

R1: bt Johnson 6-3 6-2 6-2
R2: bt Krajinovic 6-1 6-4 6-1
R3: bt Millman 4-6 7-6 (7-2) 6-4 4-6 7-6 (10-8)
R4: bt Fucsovics 4-6 6-1 6-2 6-2

Next up

Sandgren finds himself in a familiar position. The 28-year-old will contest his second Australian Open quarter-final following his 2018 run. Sandgren upstaged 12th seed Fabio Fognini in four sets on Sunday. This will be the first meeting between Sandgren and Federer.

Draw

A blockbuster semi-final against defending champion Novak Djokovic is on the horizon for Federer. Djokovic must see off Milos Raonic to make that happen. The iconic pair played out a remarkable Wimbledon final, won by Djokovic, last year.

What he said

"I'm very happy how I'm feeling considering my age, considering everything I've gone through throughout my career. The toughness of the first real tough match of the season for me after having not played these kinds of matches for some time, it's nice to see that the work I did in the off-season paid off."

Federer eventually overcame a leg injury and his American opponent 6-3 2-6 2-6 7-6 (10-8) 6-3 in three hours, 31 minutes on Rod Laver Arena.

But Sandgren squandered seven match points in the fourth set, including four in an extraordinary tie-break.

We take a closer look at the match points Federer saved.

First match point: Federer serving at 4-5, 40-AD in fourth set
With a second serve to play with, Sandgren gets into the point and a deep backhand is returned by Federer. But the American pulls the trigger too early with his next chance, sending a backhand into the net as he tries to go down the line.

Second match point: Federer serving at 4-5, 40-AD in fourth set
Another second serve to aim at, Sandgren gets into the point, but it is Federer dictating before the American sends a tame forehand wide.

Third match point: Federer serving at 4-5, 40-AD in fourth set
Sandgren manages to get into the point despite a good Federer serve down the middle before hitting the tape with a forehand from behind the baseline.

Fourth match point: Federer serving at 3-6 in fourth-set tie-break
Another Federer second serve, Sandgren controls the first part of the point from the baseline. However, he allows the Swiss great to work his way back into it before putting a backhand into the net as he tried to change direction by going down the line.

Fifth match point: Federer serving at 4-6 in fourth-set tie-break
Federer lands an excellent serve that Sandgren cannot return.

Sixth match point: Sandgren serving at 6-5 in fourth-set tie-break
Finally an opportunity on serve, Sandgren attacks but just cannot do enough with a backhand volley. He reaches for a forehand volley but Federer has an open court to play into to level the tie-break.

Seventh match point: Federer serving at 6-7 in fourth-set tie-break
Once again, Federer misses a first serve. They rally backhand-to-backhand as Sandgren shows good depth before Federer eventually changes the direction during a 19-shot point. But it is a slice that undoes Sandgren, whose return goes halfway up the net.

Emerging star Musetti defeated American qualifier Mmoh 6-4 6-4 to set up a second-round meeting with 23rd seed Benoit Paire.

Former US Open champion Marin Cilic also progressed in a three-set victory over Federico Coria, while Thanasi Kokkinakis, Sebastian Korda, Tennys Sandgren and Jordan Thompson were other winners.

Former top-five player Kevin Anderson was among those to bow out in the first round of the ATP 1000 event.

STAR ON THE RISE

Italian teenager Musetti continued his rapid rise with a hard-fought victory over Mmoh.

The 19-year-old Musetti reached the semi-finals of last week's Mexican Open, where he beat both Diego Schwartzman and Grigor Dimitrov en route to the semi-finals.

This week, Musetti battled past wildcard Mmoh in one hour, 38 minutes.

"Last week was a fantastic run in Acapulco," Musetti said in his on-court interview. " I played a really good match, it was a tough match.

"I think my lethal weapon is the backhand down the line."

CILIC SLICE OF FORTUNE

Former world number three Cilic secured his place in the second round with a 6-3 2-6 6-4 victory against Federico Coria.

However, Cilic – the 2014 US Open winner – had a huge slice of luck to claim a break back in the first.

The Croatian got lucky down a break at 2-1 but up 30-40 in the first when he mishit his overhead attempt, striking his frame and bobbling over for a drop shot winner to level.

"It was important for me to keep my head down, keep the focus and just try to get the best level I could today," Cilic said.

FOND MEMORIES FOR THANASI

Australian qualifier Kokkinakis' fond memories in Miami returned with a 6-3 6-3 win over Shintaro Mochizuki as he continues his positive return from a shoulder injury.

Kokkinakis beat then-world number one Roger Federer in Miami in 2018.

Korda won his Miami Open debut match, triumphing 6-3 6-0 over Radu Albot to set up a meeting with 10th seed Fabio Fognini.

Jordan Thompson will face Milos Raonic after accounting for Federico Delbonis 7-6 (8-6) 6-4 in two hours, 12 minutes.

Sandgren – a two-time Australian Open quarter-finalist – got past Pedro Martinez 6-4 2-0, with the Spaniard retiring.

Wimbledon and US Open runner-up Anderson was a surprise casualty, going down 7-6 (8-6) 7-5 to lucky loser Damir Dzumhur.

"I know that my game can be much better than what I'm showing right now and my position in the ATP Rankings can be much better," Dzumhur said.

The top seed – beaten by Rafael Nadal, who is in the same half of the draw, in the Paris final last year – had won his previous 16 first-round contests at the French Open, and there never appeared to be any danger of him failing to extend that record on Court Philippe-Chatrier.

Indeed, this meeting lasted under two hours, with the world number one cruising through 6-2 6-4 6-2 without conceding serve and while hitting 33 winners in the process.

It also brought up his fourth career win over Sandgren, maintaining a 100 per cent record over the world number 66. Pablo Cuevas awaits in round two.

Sandgren was a break down in a hurry as Djokovic breezed through the first set in just 31 minutes.

The 34-year-old – a five-time Roland Garros finalist who claimed his solitary title at the event in 2016 – grew frustrated in the second set as he made nine unforced errors and offered up six break points, yet he saved them all.

It evidently demoralised Sandgren, who had put everything into trying to draw level, and the American swiftly found himself 4-1 and two breaks down in the final set, with Djokovic moving through the gears.

A sloppy shot into the net cost Djokovic his first match-point opportunity at 5-2 up, yet he made no mistake as he served out for the win – Sandgren's overhit cross-court forehand rounding off a one-sided contest.

Data Slam: Super Djokovic serves up a treat

Eighteen-time grand slam champion Djokovic may not have needed to live up to his own lofty standards, but his service game was typically excellent in the evening session. He landed 49 of 73 first serves, helping him to win 86 per cent of his first-serve points (42/49). 

WINNERS/UNFORCED ERRORS

Djokovic – 33/21
Sandgren – 25/27

ACES/DOUBLE FAULTS

Djokovic – 4/2
Sandgren – 5/1

BREAK POINTS WON

Djokovic – 5/11
Sandgren – 0/6

All four Frenchmen in action on Monday were knocked out in Lyon, including 2018 finalist Gilles Simon.

Aljaz Bedene knocked out the world number 68 in straight sets, two breaks of serve in each enough to secure a 6-2 6-3 triumph after one hour and 13 minutes on court.

Sebastian Korda overcame both Pierre-Hugues Herbert and the rain to progress to the second round, a 7-6 (7-5) 6-4 triumph wrapped up quickly following a delay.

Having been 5-4 ahead in the second set when play was halted, Korda clinched victory on his first match point upon the resumption, in the process snapping a run of four successive defeats on the ATP Tour.

Cameron Norrie will take on top seed Dominic Thiem next after his 7-5 6-3 win against Corentin Moutet, while Ugo Humbert let slip a one-set lead as he was beaten by Yoshihito Nishioka.

Meanwhile, at the Geneva Open, there was a maiden victory for French teenager Arthur Cazaux as he came out on top against compatriot Adrian Mannarino.

The 18-year-old held his nerve in a decider despite this being his first tour-level contest; Reilly Opelka or Pablo Cuevas will be next up in the event.

As for Federer, he will begin his campaign on Tuesday, the 39-year-old having played just two matches so far this year after undergoing two knee operations in 2020.

The Swiss superstar now knows he will be up against Pablo Andujar, who overcame Australia's Jordan Thompson in straight sets.

Tennys Sandgren saw off Salvatore Caruso 6-3 6-4, while Dominik Koepfer came through a tight tussle with Benoit Paire that spanned two hours and 39 minutes.

World number 12 Rublev, a two-time winner on the ATP tour this year, is seeded fifth in Hamburg and made light work of Sandgren.

Russia's Rublev broke his American foe three times and did not offer up a single break point on his own serve as he won 6-3 6-3 in an hour and nine minutes.

Elsewhere it was a productive day for qualifiers in the round of 32, with Pablo Cuevas and Jiri Vesely respectively seeing off Taylor Fritz and Gilles Simon in straight sets.

Despite the woes of his compatriots Sandgren and Fritz, Tommy Paul prevailed in a topsy-turvy encounter with Kevin Anderson.

The former Wimbledon and US Open finalist inflicted a bagel upon Paul to level matters in the second set but the world number 59 regrouped to triumph 6-4 0-6 6-4 - the big serving Anderson's 14 aces to his opponent's one counting for little in the final analysis.

The 22-year-old claimed a 6-4 7-6 (7-4) victory to set up a meeting with Tennys Sandgren in the next round.

Following Ruud onto Centre Court, the American beat Spain's Jaume Munar 7-6 (7-3) 7-5 in just over two hours.

Sixth seed Karen Khachanov is also safely through, although he surrendered a set in beating French qualifier Lucas Pouille 7-6 (9-7) 3-6 6-4.

But Dusan Lajovic, seeded eighth, was not quite as fortunate.

Lajovic, ranked 41st in the world, was beaten 6-4 7-6 (7-2) by Slovakian qualifier Lukas Klein (ranked 256).

Feliciano Lopez came out on top of battle of Spaniards in the round of 32, beating Nicola Kuhn 6-1 7-6 (7-4).

Their compatriot Roberto Carballes Baena is in with a chance of joining them on Tuesday after seeing his clash with Sam Querrey paused due to light with both players having taken a set.

Elsewhere, Corentin Moutet beat Lloyd Harris to set up a meeting with top seed Daniil Medvedev, while Jiri Vesely and Stefano Travaglia also progressed.

Monday's other scheduled ATP event in Eastbourne saw play cancelled due to rain, with the scheduled match between Jo-Wilfried Tsonga and Egor Gerasimov pushed back as a result.

The American, twice a quarter-finalist at Melbourne Park, initially posted to social media on Wednesday that he had tested positive for the virus for a second time. 

Although his first instance of having the illness was recorded in November, the 29-year-old's participation in the tournament appeared to be in doubt. 

But, as he continued to update followers through the day, it emerged he had been allowed to board his flight. 

Writing on Twitter, he said: "Wait hold on I think they are trying to get me on 15 min [sic] after the plane was supposed to depart.. my bags still aren't checked lol." 

A follow-up read: "Wow I'm on the plane. Maybe I just held my breath too long. Craig Tiley [Tennis Australia] is a wizard." 

Some expressed concerns about the possibility of Sandgren potentially spreading the virus to fellow passengers and then locals once he arrives in Australia. 

But a statement from the Australian Open has looked to reassure people that players' infectiousness is checked prior to boarding flights. 

It read: "In the case of Tennys Sandgren, who has self-disclosed that he previously tested positive in late November, his medical file had to be reviewed by Victorian health authorities. Upon completion of that review he was cleared to fly.

"Any recovered case must go through this process in order to have an opportunity to travel here for the Australian Open. No one can travel without either proof of a negative test or this special clearance from authorities confirming they are not infectious. 

"Upon arrival all players are immediately placed in a secure quarantine environment for 14 days under the authority of COVID Quarantine Victoria, and will undergo a more rigorous testing schedule than most returning travellers." 

An earlier statement issued by the tournament organisers in reply to Sandgren's tweets said: "Some people who have recovered from COVID-19 and who are non-infectious can continue to shed the virus for several months. 

"Victorian Government public health experts assess each case based on additional detailed medical records to ensure they are not infectious before checking in to the charter flights. 

"Players and their teams are tested every day from their arrival in Australia, a much stricter process than for anyone else in hotel quarantine." 

The first grand slam of the year is due to begin on February 8 after being delayed due to the pandemic. 

Initially it was to run from January 18-31 but was pushed back to help give qualifiers time to travel and complete a two-week quarantine in Australia prior to warm-up events getting under way at the end of the month. 

Players at Melbourne Park will have to follow strict guidelines and protocols, including a five-hour limit on training with a maximum of one team member. 

The teams must stay in their hotel for the other 19 hours of every day, and players have to return six negative COVID-19 tests before being allowed to play.

French Open quarter-finalist Sinner took just 61 minutes to seal a 6-1 6-2 victory against Duckworth, who replaced Hubert Hurkacz after the Pole withdrew due to food poisoning. 

The 19-year-old Italian reached a career high 46 in the rankings following his exploits at Roland Garros and cruised past Duckworth after fending off two break points in a 12-minute game at 2-2 in the second set. 

Sinner will go up against qualifier Pierre-Hugues Herbert in round two after the Frenchman defeated Tennys Sandgren 6-3 3-6 6-3 at the ATP event on Tuesday. 

Zverev defeated Felix Auger-Aliassime in the final of last week's tournament in Cologne and will begin his bid for a second straight title against Millman after the Australian overcame Fernando Verdasco 6-4 6-2. 

At the European Open in Antwerp, Alex De Minaur came from a set down to defeat veteran Richard Gasquet 3-6 7-6 (7-5) 6-3. 

When serving for the set in the second set, Gasquet produced an unforced error following a reactive backhand from De Minaur. He then double faulted at 5-5 in the tie-break and the Australian eighth seed dished out the ultimate punishment. 

Federico Coria stepped in after Kei Nishikori withdrew due to a right shoulder injury and the Argentinian was comfortably beaten 6-2 6-3 by Pablo Andujar. 

Now unranked, Sock needed a wildcard into the ATP 250 tournament and suffered a 6-3 6-4 loss to fellow American Marcos Giron.

A former world number eight, Sock won just one singles match last year – at the Laver Cup.

Giron created 10 break points and converted four on his way to victory in 76 minutes.

Coming off a run to the Australian Open quarter-finals, Sandgren suffered a 6-7 (5-7) 6-3 7-6 (7-3) loss to Steve Johnson.

Sandgren squandered seven match points in a last-eight loss to Roger Federer in Melbourne and the fifth seed was edged by Johnson.

Sixth seed Miomir Kecmanovic and Italian veteran Andreas Seppi posted wins over Tommy Paul and Damir Dzumhur respectively.

At the Argentina Open, Casper Ruud was the only seed in action and eased past Pablo Andujar 6-2 6-3.

Pablo Cuevas, Federico Delbonis and Thiago Monteiro also moved into the second round.