DELRAY BEACH, Fla. (AP) — John Isner held off an upset bid by Dudi Sela of Israel on Thursday night to advance to the quarterfinals of the Delray Beach Open after No. 3 seed Kei Nishikori of Japan exited the tournament because of a left hip injury.
The second-seeded Isner squandered four match points in the third set after leading 4-1, but the 6-foot-10 American rallied from a 5-2 deficit to prevail in the tiebreaker for a 3-6, 6-1, 7-6 (5) victory that earned him a spot in the quarterfinals for the third consecutive year.
"More times than not, when I'm up 4-1, I close it out," said Isner, who is 5-0 in his three-set matches this season but is playing in his first tournament since exiting the Australian Open with an ankle injury last month. "It definitely didn't need to go to 5-5 when I was up 4-1. I put a lot of stress on myself when I do that."
The world No. 13 will face American qualifier Rhyne Williams on Friday night. Williams ousted wild-card Marcos Baghdatis of Cyprus 6-7 (7), 6-4, 6-2 in Thursday's nightcap to reach his second ATP quarterfinal.
Nishikori's bid to win his second consecutive ATP title came to an abrupt halt Thursday afternoon when the top-ranked Asian was forced to retire during the first set of his second-round match because of a left hip flexor injury.