Novak Djokovic again overcame the challenge of a fellow home favourite to advance to the semi-finals at the Serbia Open on Thursday. 

The world number one had battled from a set down against Laslo Djere 24 hours earlier and was once more made to work hard for his win versus Miomir Kecmanovic. 

The seventh seed took the opener without facing a break point and led early in the second set too. 

But Kecmanovic could not hold off Djokovic, who recovered to win 4-6 6-3 6-3 and reach the last four for the fourth time in five campaigns in Belgrade. 

After two victories in two nights against Serbians for the two-time winner, Djokovic is on a 10-0 run in matches with his compatriots and 27-4 all-time. 

The 20-time grand slam champion also has a 36-6 record in Serbia and has particularly enjoyed the "strange" opportunity to face his countrymen in front of a home crowd. 

"It's a very strange feeling, sharing the court with your compatriots," he said. "Obviously the crowd was phenomenal for both players in yesterday's match and today's. 

"They're very rare occasions when I'm able to play at home and experience this atmosphere, so I'm trying to enjoy every single moment." 

Djokovic is the last Serbian remaining in the tournament, though, and takes on third seed Karen Khachanov – a winner against Thiago Monteiro – in the semis. 

There remain two quarter-finals to play on Friday, as Andrey Rublev faces Taro Daniel while Fabio Fognini welcomes the challenge of Oscar Otte. 

Meanwhile, there were only two matches completed at the Barcelona Open due to rain, but Ilya Ivashka ensured fans were rewarded for their patience as he took Stefanos Tsitsipas the distance. 

Ivashka eventually went down 6-1 4-6 6-2 to the top seed in a heavily delayed second-round contest. 

Novak Djokovic edged into the quarter-finals of the Serbia Open by defeating Laslo Djere 2-6 7-6 (8-6) 7-6 (7-4) in a tense encounter in Belgrade. 

World number one Djokovic was in danger of losing three straight ATP Tour matches for the first time in over four years when he surrendered the opening set to his fellow Serbian in front of an adoring crowd. 

The 20-time grand slam winner was two points away from defeat in the second-set tie-break but managed to force a decider by converting set point at the sixth attempt.

And Djokovic needed another tie-break to get the job done, with Djere paying the price for a series of errors as he missed out on a chance to claim a famous victory. 

Next up for Djokovic, who bounced back from successive defeats to Jiri Vesely and Alejandro Davidovich Fokina in Dubai and Monte Carlo respectively, is Miomir Kecmanovic. 

Seventh seed Kecmanovic faced little resistance from John Millman as he claimed a 6-4 7-6 (7-5) success, while Karen Khachanov was granted a walkover against Roman Safiullin. 

At the Barcelona Open, Carlos Alcaraz advanced to the third round courtesy of a 6-1 2-6 6-2 victory over Kwon Soon-woo. 

He will face Jaume Munar for a place in the quarter-finals following the wildcard's 6-1 6-4 triumph against ninth seed Nikoloz Basilashvili. 

Felix Auger-Aliassime was taken the distance by Carlos Taberner but eventually closed out a 6-1 3-6 6-4 success. His reward is a meeting with Frances Tiafoe, who beat Hugo Dellien 7-6 (7-3) 6-1. 

Lloyd Harris defeated Albert Ramos Vinolas 6-3 6-4, while Alex De Minaur, Emil Ruusuvuori, Pablo Carreno-Busta and Marton Fucsovics also advanced. 

Inclement weather brought a halt to top seed Stefanos Tsitsipas' meeting with Ilya Ivashka after just one game, while Grigor Dimitrov was up a break in the third set of a clash with Federico Coria.

Dominic Thiem suffered defeat in his first ATP Tour match since June, losing at the Serbia Open to John Millman.

Thiem has been out of action since suffering a right wrist injury and the former world number three was able to claim the second set in his comeback match.

But he could not avoid a 6-3 3-6 6-4 defeat in a contest that lasted two hours and 35 minutes.

Speaking afterwards, Millman said: "It is great to be back here. I was looking forward to coming back and [playing]. All credit to Domi.

"I can't claim it was one of my biggest wins because he is just coming back from injury and I know how hard that is, coming back from three surgeries myself.

"I know it has been tough for Domi but the game is better having him back. Especially on this surface. I have got to take this win because when he gets better and fitter, it is going to be tough."

Next up for the Australian is Miomir Kecmanovic.

NextGen star Jiri Lehecka booked a meeting with second seed Andrey Rublev by beating Henri Laaksonen, while Filip Krajinovic overcame David Goffin.

At the Barcelona Open, fourth seed Cameron Norrie had to come back from a set down to see off Egor Gerasimov, though his 12th seeded fellow Briton Dan Evans lost to Lorenzo Musetti.

There were routine wins for second seed Casper Ruud, sixth seed Diego Schwartzman and 11th seed Lorenzo Sonego.

Cristian Garin was on the end of a shock thrashing by Denmark's Holger Rune in the first round of the Serbia Open on Monday.

The Chilean fifth seed, who was the highest-ranked player in action, is regarded as one of the ATP Tour's best on clay but hardly got a look-in as 18-year-old Rune emerged with an impressive 6-3 6-1 win.

Rune has risen to a career-high 72 in the ATP rankings and showed every sign that he will continue to climb over the season as he produced an aggressive performance that saw him take six of 17 break points.

Playing in only his fifth ATP Tour match on clay, Rune needed just an hour and 25 minutes to see off Garin – the winner of five tour-level titles on the surface – and set up a second-round clash with either Dusan Lajovic or Taro Daniel.

Sixth and seventh seeds Fabio Fognini and Miomir Kecmanovic avoided similar shocks, though their respective wins were wildly different.

Kecmanovic crushed veteran Richard Gasquet 6-0 6-3, while Fognini was forced to overturn a one-set deficit in his defeat of fellow Italian Marco Cecchinato 6-7 (5-7) 6-2 6-2.

No seeds were in action at the Barcelona Open, but Italian prospect Lorenzo Musetti enjoyed a hard-fought 7-5 7-5 defeat of Argentina's Sebastian Baez to seal his spot in the second round.

The 20-year-old is now 5-2 for the clay season and will go up against Dan Evans next. Joining Musetti in progressing is another promising youngster in Brandon Nakashima, who beat Nicolas Alvarez Varona 7-6 (8-6) 6-3 to tee up a clash with number two seed Casper Ruud.

Mackenzie McDonald, Elias Ymer, Kwon Soon-woo and Federico Coria were among the other victors, while retiring 2004 champion Tommy Robredo bowed out with a 6-1 6-1 loss to Bernabe Zapata Miralles.

Rafael Nadal won the Barcelona Open for the 12th time after saving a championship point in a to end Stefanos Tsitsipas' perfect record on clay this year in a thrilling final.

World number three Nadal, playing just his third tournament of the year, is gearing up for a tilt at a record-extending 14th French Open title.

By defeating the man who landed the Monte Carlo Masters title last week, Nadal showed he is moving through the gears on his favourite surface before heading to Paris.

He won 6-4 6-7 (6-8) 7-5 to maintain his 100 per cent record in finals at this tournament on home soil, but Tsitsipas was left to reflect on a missed opportunity after the 20-time grand slam champion fended off a championship point at 5-4 in the final set.

Nadal trailed 4-2 in the opening set as Tsitsipas signalled he was up for the challenge and brimming with confidence, but back came the 34-year-old to sweep up the next four games.

Tsitsipas broke first in the second set too, inching 2-1 in front, and the Greek looked every bit a warrior capable of living with the best for much of the contest.

It was a rout when these two met in the Barcelona final three years ago, Nadal dropping only three games, but here he needed to work far harder, in what was the 69th clay-court final of his stellar career.

Tsitsipas beat Nadal from two sets down in the Australian Open quarter-finals in February, so dropping the opener here was not cause for panic, but nor was gaining the early break in the second any reason to be confident he would be taking the match to a decider.

Nadal duly broke back but then let two championship points slip by in the 10th game, with Tsitsipas serving. A smash followed by a superb drop volley from Tsitsipas meant the match remained alive.

Tsitsipas could not convert 0-40 on Nadal's serve in the next game, but he won a thrilling tie-break to take the contest all the way.

There was not a solitary break point in the decider until Tsitsipas was a point away from claiming the title in the 10th game, but the King of Clay dug in to hold.

He rubbed salt in the wounds by securing the elusive break in the next game and dropped to the clay in delight after serving it out, ending a pulsating showdown that was finally settled in three hours and 38 minutes.

Rafael Nadal fended off Kei Nishikori to reach the quarter-finals of the Barcelona Open along with the in-form Stefanos Tsitsipas on Thursday.

Top seed Nadal secured an opening-set bagel in just 30 minutes, but Nishikori hit back to force a decider before the 20-time grand slam champion prevailed 6-0 2-6 6-2.

Nishikori hit only three winners as he was blown away in the first set, but broke twice in the second to ensure Nadal was taken to three sets in back-to-back matches for the first time in this tournament – having overcome Ilya Ivashka in the second round.

The world number three saved three break points from 0-40 down in the final set and Nishikori saw another two come and go, with a more clinical Nadal breaking twice to advance.

Nadal will now face unseeded Brit Cameron Norrie, who also won the first set 6-0 and was 5-3 down to David Goffin in the second when the Belgian retired due to a leg injury.

Newly-crowned Monte Carlo Masters champion Tsitsipas defeated Alex de Minaur 7-5 6-3, stretching his straight-sets winning streak to seven matches.

Next up for the second seed is a meeting with Felix Auger-Aliassime, who beat fellow Canadian Denis Shapovalov 6-2 6-3, while Jannik Sinner beat Roberto Bautista Agut 7-6 (11-9) 6-2.

Andrey Rublev, Diego Schwartzman and Pablo Carreno Busta also made it through.

Two seeds fell in the Serbia Open, with Federico Delbonis taking out Dusan Lajovic 6-3 2-6 6-4 and Taro Daniel defeating John Millman 3-6 6-2 6-3.

Gianluca Mager moved into the quarter-finals at the expense of Alexei Popyrin and Aslan Karatsev battled past Aljaz Bedene 6-3 4-6 7-6 (7-5) in Belgrade.

Novak Djokovic thought he was "pretty flawless" in his first match of the Serbia Open, but Rafael Nadal was given a scare in his clash with qualifier Ilya Ivashka at the Barcelona Open.

World number one Djokovic suffered a shock third-round exit to Dan Evans at the Monte Carlo Masters last week but ruthlessly dispatched Kwon Soon-woo 6-1 6-3 in his home city of Belgrade.

Djokovic broke his opponent five times to set up a meeting with eighth seed and fellow Serbian Miomir Kecmanovic, who battled past qualifier Arthur Rinderknech in three sets, in the quarter-finals.

"I thought it was a pretty flawless performance," Djokovic said. "I moved well, I was mixing up the pace quite well, making him play. I served well in the important moments, [and] overall I just felt great."

On playing in front of his family and friends, the two-time Serbia Open champion added: "It gives you an extra push, an extra motivation, energy to really give your best and leave it all out on the court.

"I think also that made me feel comfortable and confident on the court and I played really good. I'm really pleased with the quality of tennis."

Second seed Matteo Berrettini defeated fellow Italian Marco Cecchinato 6-4 6-3 and will face either Filip Krajinovic or Nikola Milojevic in the last eight of the clay-court tournament.

Over in Barcelona, Nadal – an 11-time champion at the event – was out to make a statement after a rare defeat on the dirt to Andrey Rublev in Monte Carlo.

But the 'King of Clay' needed two hours and 20 minutes to fight back against the unheralded Ivashka 3-6 6-2 6-4 to reach the round of 16, where he will face Kei Nishikori. Nadal is now 62-4 at a tournament where he once won 41 straight matches.

Second seed and Monte Carlo champion Stefanos Tsitsipas hammered Jaume Munar 6-0 6-2, while third seed Rublev - runner-up to the Greek on Sunday - joined Pablo Carreno Busta (6) and Alex De Minaur (14) in making it through.

Evans was unable to follow up his run in Monte Carlo with the 16th seed beaten by Corentin Moutet in a lengthy three-setter, while Fabio Fognini (9) was defaulted for unsportsmanlike conduct after verbally abusing a line official when trailing 6-4 4-4 to Spanish qualifier Bernabe Zapata Miralles.

Jannik Sinner set up a clash with Roberto Bautista Agut at the Barcelona Open as he vowed to keep making progress after cracking the top 20 for the first time.

Italian 19-year-old Sinner is a fast-rising new star of the men's game and now has a ranking to match his age. However, he was put in his place by Novak Djokovic last week in Monte Carlo, before the world number one was himself dealt a jolting defeat by Dan Evans.

Sinner sped past Belarusian Egor Gerasimov in the first round in Barcelona on Tuesday, winning 6-3 6-2, and it will be wily world number 11 Bautista Agut who stands in his way of going deeper into the tournament.

In two meetings on hard courts this season, Sinner has edged out 33-year-old Spaniard Bautista Agut in tight deciding sets, and now they face a reunion on clay.

"He lost in Dubai against me, he lost in Miami against me, now we play once more here, so it's quite a small period of time," said Sinner.

"We're playing now our third match already, so it's going to be a very tough match. He is very, very solid. I never played against him on clay. I'm trying to be ready in the best possible way."

Bautista Agut barged past fellow Spanish player Pablo Andujar, scoring a 6-4 6-0 win.

Sinner was proud to enter the ATP top 20 this week but sees it as just a step on his journey, saying: "Obviously it's a good number, but for me at the moment not that important."

He added, quoted on the ATP website: "[I'm] just trying to improve day after day with my team and trying to improve as a player and the ranking is what it is. I'm happy to be top 20 player but the road is long so a lot of work to do."

Albert Ramos-Vinolas, Lorenzo Musetti and Frances Tiafoe, who fought off 17-year-old Spanish prospect Carlos Alcaraz, were also among Tuesday's winners in Barcelona.

Star turn Djokovic begins his campaign at the Serbia Open on Wednesday when he tackles Kwon Soon-woo, with the 18-time grand slam winner having received a first-round bye.

Tuesday's play in Belgrade saw wins for, among others, Federico Delbonis, Aljaz Bedene and Miomir Kecmanovic.

Kei Nishikori's comeback surprised the former world number four, who survived a major scare to advance at the Barcelona Open.

Nishikori trailed 6-4 4-2 and was forced to break serve as Guido Pella attempted to close out the match in the second set, before sensationally rallying to a 4-6 7-6 (7-4) 6-2 win on Monday.

A two-time champion at the ATP 500 tournament on the Barcelona clay, Nishikori broke serve on three occasions in the final set en route to the second round.

"He had the match today at 6-5, serving [for the match]," said Nishikori. "He was much better in the first and second [sets] and 3-0 up in the tie-break. I don't know how I fought through. [In the] third set, I was playing much better.

"I was making so many unforced errors in the first and second [sets]. Maybe he got a little bit tired and I was playing strong in the third set. I want to take that to the next round… The way I fought today and the way I played in the third set was good."

Next up for 2014 US Open finalist Nishikori is 13th seed Cristian Garin.

Ilya Ivashka topped Tallon Griekspoor 6-3 6-1 and the qualifier's reward is a showdown with top seed and 20-time grand slam champion Rafael Nadal.

Cameron Norrie, Pablo Andujar, Jeremy Chardy, Pierre-Hugues Herbert, Jaume Munar, Federico Gaio, Egor Gerasimov and Bernabe Zapata Miralles all advanced to the last 32.

At the Serbia Open, seeds Filip Krajinovic and John Millman booked their spots in the round of 16.

With the ATP 250 tournament being staged for the first time since 2012 and headlined by world number one Novak Djokovic, Serbian fifth seed Krajinovic overcame Stefano Travaglia 7-5 5-7 6-3 in a Belgrade rollercoaster.

Millman – the Australian seventh seed – took down local wildcard Danilo Petrovic 7-5 6-4 as Marco Cecchinato and Nikola Milojevic won through.