LONDON, July 9 (Reuters) - Kei Nishikori overcame elbow trouble in the opening set to win a marathon match 4-6 7-6(5) 7-6(10) 6-1 against a limping Ernests Gulbis and reach his first Wimbledon quarter-final at the tenth attempt on Monday.
Latvian qualifier Gulbis, a former world number 10 also looking for his first quarter-final at Wimbledon, gave as good as he got in a ding-dong battle over three sets before hurting his knee in the third-set tiebreak.
Japanese former world number four Nishikori, seeded 24th, was troubled by his right elbow during the first set which he lost after being broken in the fifth game.
Gulbis, who won the ace count 18-7, beat Nishikori with a chip at the net to give himself two set points and took it on the first.
The next two sets were a battle of attrition with Gulbis moving his opponent from side to side and hitting crosscourt backhand winners, while Nishikori hung in on the rallies.
Nishikori took the second set after going into a 5-1 lead in the tiebreak. A fine chip gave the Japanese a set point at 6-3 but Gulbis rallied with an ace followed by a neat drop shot, before Nishikori sealed it when the Latvian returned long.
The third set tiebreak was more dramatic with Gulbis going off for treatment after slipping and hurting his left knee and coming back on with it heavily bandaged.
The Latvian saved two set points with some strong returns but both players made unforced errors, Gulbis missing a volley and Nishikori serving two double faults before the Japanese finally clinched it 12-10 after almost three and a half hours.
Gulbis, who had won three five-set matches to get to the fourth round including his upset over fourth seed Alexander Zverev, quickly fell 5-0 behind in the fourth set but managed to hold serve in the sixth game after saving a match point.
Nishikori, runner-up at the 2014 U.S. Open, won the Court Two match on the second match point in the following game when Gulbis, now limping badly, hit a return long. (Reporting by Rex Gowar Editing by Christian Radnedge)