Andy Murray is considering withdrawing from the Citi Open after feeling he was put in an unreasonable position by playing into the early hours of Friday morning.
Rain delays disrupted the schedule in Washington DC, meaning Murray and opponent Marius Copil did not take to the court until midnight, before a three-hour marathon took the match beyond 03:00 local time.
An emotional Murray ultimately progressed 6-7 (5-7) 6-3 7-6 (7-4), setting up a quarter-final meeting with Alex De Minaur, but he was not happy with the organisers afterwards.
Having only recently returned from a lengthy absence due to a hip injury, Murray suggested it would be difficult for him to be expected to play again later on Friday.
"Finishing matches at three in the morning is not good. It's not good for the players. It's not good for anyone, I don't think, involved in the event," Murray said. "It's not good for fans, TV, nobody.
"Not playing [against De Minaur], potentially, is possible.
"I'm giving my view right now as someone who's just come back from a very, very long injury lay-off. I don't think I should be put in a position like that, when you're expected to come out and perform the next day. I don't think it's reasonable.
"And I'm disappointed with that, because I know that the weather's tricky and I know it is for the scheduling, but it's a very difficult position to be in. [The hip] doesn't feel great just now.
"I don't know how you are expected to recover from that. By the time you're done with all your recovery and stuff, it's going to be five-thirty, six o'clock in the morning.
"I'd obviously try to sleep as late as I can, but with the way your body clock is and stuff, you might get a few hours' sleep. It's not good. And it's basically like playing two matches in a day."
Murray was seen sobbing into a towel court-side for several minutes after the win over Copil, which he explained was triggered simply by his relief at surviving the exhausting encounter.
"It was just the emotions coming out at the end of an extremely long day and a long match," he said.