China's Zheng Qinwen reached the US Open quarter-finals at 02:15am on Monday in a record late finish for a women's match at the tournament.
Seventh-seed Zheng defeated Croatian Donna Vekic 7-6 (7-2) 4-6 6-2 to beat the previous record of 02:13am from 2021, when Maria Sakkari beat Bianca Andreescu in a last-16 tie.
Zheng, who beat Vekic last month to win Olympic gold in the singles in Paris, will now face world number two Aryna Sabalenka on Tuesday.
The late finish drew criticism from 2012 US Open champion Andy Murray, who said the scheduling was "amateurish" and "a total mess", calling for the Grand Slam organisers to "sort it out".