World number 120 Illya Marchenko has progressed into the second round of the US Open after 16th seed Gael Monfils retired in the third set.

With one set apiece, Marchenko was 5-0 ahead in the third before the Frenchman bowed out, having suffered an elbow injury earlier in the match.

Monfils, who reached the quarter-finals last year, inflicted a break of serve in the third and seventh games en route to a 6-2 first-set lead.

He then slipped on the baseline and landed on his elbow as Marchenko broke serve to move 3-1 ahead in the second - and he would not be caught.

The Ukrainian levelled up the match by winning the second set 6-4, and then moved one game away from the lead before his opponent retired.

Monfils was the fifth player to retire from round one.