Keys after midnight first round win

New York - American eighth seed Madison Keys reached the US Open second round on Monday beating compatriot Alison Riske in a tie which ended at 01:48am, the latest finish to a women's match in tournament history.

Keys triumphed 4-6, 7-6 (7/5), 6-2 and goes on to face fellow American Kayla Day for a place in the last 32.

Day, just 16 and ranked 374 in the world, went through when opponent Madison Brengle retired in the second set with an arm injury.

Keys fired 60 winners and 60 unforced errors with 13 aces.