Novak Djokovic brushed off the challenge of Spain's Feliciano Lopez to reach his ninth consecutive US Open semi-final.
Djokovic has only lifted the title once at Flushing Meadows in that time but the top seed remains on course to improve his tally after beating Lopez 6-1 3-6 6-3 7-6 (7/2).
Lopez threatened a comeback after clinching the second set but the world number 19 made too many unforced errors — 48 to Djokovic’s 17 — and the Serb held on to go through.
Djokovic will now face defending champion Marin Cilic, who outlasted France's Jo-Wilfried Tsonga in five sets and beat Roger Federer in the final last year.
Cilic has a miserable record against Djokovic, having never beaten the world number one in 13 attempts, but the Croat feels at home in New York after 12 consecutive victories here.
“I would think Cilic takes more confidence because of the fact that he won his first grand slam title last year in New York,” Djokovic said.
“He hasn’t lost a match, for 12 matches in a row so I’m sure that he feels confident.
“He won today a really close match after a couple of five-setters he had already in this tournament.
“But he has a big serve. I think around 30 aces he had today, so the serve gets him out of trouble. I know him very well. I have played with him many, many times.”
Cilic spurned three match points in the fourth set as Tsonga forced a decider but the Croat kept his composure in the fifth to win 6-4 6-4 3-6 6-7 (3/7) 6-4.
The victory leaves Cilic two wins away from becoming the first man to defend the US Open title since Federer claimed five in a row between 2004 and 2008.
“I decided to stay mentally tough,” Cilic said. “I was thinking about the third and fourth set. I didn’t play poorly.
“Jo came up with amazing shots in the critical points, especially on all three match points that I had, he played great points.
“I didn’t choose any bad shots or play bad points. I just kept going with it. I stuck with my plan and stayed mentally tough.”
Tsonga appeared riled at the end of the match as he offered his opponent a noticeably short handshake before making a swift exit from Arthur Ashe Stadium.
Cilic admits he was surprised by the world number 18’s reaction but was unable to offer an explanation.
“I was surprised, actually,” Cilic said.
“I really don’t know why. But, you know, Jo shook my hand, and said, ‘Congratulations’. But that was it.
“I don’t know for the rest. If I provoked him or not I have no idea. I hope not.”
