Novak Djokovic showed he is very much the man to beat at the US Open with a stunning display to defeat Juan Martin Del Potro in straight sets in the quarter-finals.
The 6-2 7-6 (7/3) 6-4 scoreline does not remotely tell the story of a match where 2009 champion Del Potro threw everything at last year's winner only to see it come back with interest.
Djokovic said: "Even though it was straight sets it was much closer than that. He's a great player. I was lucky in the second set.
"We played some incredible points. It's always entertaining to play at night - so much fun. This is very special and I'm really happy to be in the semi-finals."
Djokovic will now play fourth seed David Ferrer, who beat Janko Tipsarevic in another classic earlier on Thursday, in a rematch of a last-four clash from 2007.
Djokovic lost to Roger Federer in the final that year but, with the world number one knocked out by Tomas Berdych on Thursday, the second seed assumed the favourite's mantle.
So easy had the Serbian's progress been until this point, it was difficult to tell how well he was playing.
Djokovic had seemed out of sorts at Wimbledon and the Olympics, where Del Potro beat him to the bronze medal, but he showed on Arthur Ashe Stadium he is back to the form that brought him three grand slam titles last season.