Alexandr Dolgopolov came from two sets and 4-0 down to beat Canada's Jesse Levine in the first round of the US Open.
The 14th seed lost each of the opening two sets by a solitary break and then found himself a double-break down in the third.
After winning six consecutive games to claim the third set, he won the fourth without making a single unforced error.
With the momentum well and truly behind the Ukrainian, he stormed through the final set - breaking Levine twice - to take the match 3-6 4-6 6-4 6-1 6-2 in just under three hours.
Marcos Baghdatis, who overcame Germany's Matthias Bachinger in another five-set battle, will provide the opposition for Dolgopolov in round two.
