Andy Murray reached a second successive US Open semi-final on Wednesday after Croatia's Marin Cilic squandered a set and 5-1 lead to lose their quarter-final 3-6, 7-6 (7/4), 6-2, 6-0.
Third seed Murray goes on to face either world number one Roger Federer, the five-time champion who beat him in the 2008 final, or Czech sixth seed Tomas Berdych for a place in Sunday's final.
Wednesday's win was Murray's seventh in eight meetings with 12th-seeded Cilic, whose only victory over the Briton came in the fourth round in New York in 2009 when he raced to a straight-sets triumph.
But after twice serving for the second set, the 23-year-old Cilic's game fell to pieces, being broken in the fifth and seventh games of the third set.
Murray, the Olympic champion and Wimbledon runner-up to Federer this year, was quickly 4-0 ahead in the fourth set as Cilic, who came into the match having spent over three hours more on court than the Scot, wilted.
Murray broke three more times in the fourth set with the Croat winning just four points on his own serve.
Cilic ended the three-hour encounter having won just three more games from 5-1 ahead in the second set.