Nishikori, who won 6-7, 4-6, 7-6, 6-4, 7-6 after five hours and five minutes, came back from two sets down for the second time in a week and then took the deciding tie-break 10-8 after winning the last five points of the match. Carreno Busta left Margaret Court Arena screaming at the umpire, his game having fallen apart after a heated row with the official when he led 8-5 in the final tie-break.
In the quarter-finals Nishikori will face Novak Djokovic, who was also taken to the point of exhaustion before beating Russia’s Daniil Medvedev 6-4, 6-7, 6-2, 6-3 in a physical encounter that lasted three and a quarter hours and finished well after midnight.
Nishikori had had to come back from two sets down to beat Kamil Majchrzak in the first round and then needed a fifth set tie-break to beat Ivo Karlovic in the second. In the fourth round he again began slowly, while Carreno Busta was on his game from the start.
In the third set, nevertheless, Nishikori launched his fightback. After levelling at two sets apiece the Japanese made the first break of serve in the decider. He served for the match at 5-4, only for Carreno to break back.
The set went to a first-to-10-points tie-break, in which Carreno Busta went 8-5 up. The Spaniard was only two points from victory when the umpire, Thomas Sweeney, refused to replay a point after Carreno Busta claimed that he had stopped running after a line judge’s “out” call, which was subsequently over-ruled by Hawk-Eye’s cameras. Nishikori hit a winner just as the “out” call was being made and the umpire ruled that Carreno Busta was already running the wrong way and would not have got to the ball anyway.
A distracted Carreno Busta lost the next four points and the match. At the end the world No 23 threw his bag into the court before picking it up again and then shouting at the umpire as he left the arena.
At his post-match press conference Carreno Busta apologised for his reaction, though he still insisted that the umpire should have replayed the point.
“Obviously I’m very sad because after five hours fighting, the way that I left the court wasn’t correct,” he said. “I’m so sorry, because that’s not me.I tried to leave as fast as possible when I lost that last point, because I knew that at any moment I would lose my head.”
Nishikori said: “I’m getting used to these super tie-breaks. Both times I came back from a break down. I’m happy to finish like that. There were many tough moments.I just tried to fight through every point and luckily I got five points in a row in the last tie-break.”
Although Djokovic’s match was nearly two hours shorter than Nishikori’s, the world No 1 looked shattered by the end of it. Medvedev, a 22-year-old Russian who won three tour-level titles last year, is a grinder who keeps making his opponents hit the extra ball.
Djokovic edged the first set, but Medvedev set the pace in the tie-break at the end of the second. From 6-2 up the world No 19 failed to convert three set points, but after double-faulting on the third of them he was grateful to see Djokovic miss a forehand on the next point.
Kei Nishikori celebrates his win over Pablo Carreno Busta (EPA)
However, the Serb’s response could not be faulted. From 2-2 in the third set he won four games in a row and then took charge of the fourth set by breaking in the third game. At 4-3 and deuce Djokovic fell to the floor looking completely shattered, but he picked himself up to win the game and then broke serve for the seventh time to secure his victory.
Medvedev and Djokovic, who both live in Monte Carlo and often practise together, shared a joke at the net despite their tiredness. “Heasked me whether he made me sweat at all tonight,” Djokovic said with a smile. “I just laughed, because I think the answer is obvious.”
Djokovic admitted that he “didn’t feel so great” in the last 20 minutes of the match. He said he felt fatigued and also had a problem with his back but added: “I’m confident I can recover and I can be ready for my next match.”
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