A dejected Lesia Tsurenko said she was hampered by illness as she suffered a 6-1 6-1 thumping at the hands of Naomi Osaka in the US Open quarter-finals.

Wednesday's opening match on Arthur Ashe Stadium lasted just 57 minutes as 20th seed Osaka romped to a comprehensive victory.

Tsurenko had struggled with the oppressive New York heat during her last-16 triumph over Marketa Vondrousova, but wilted for different reasons against Osaka.

"Unfortunately during this tournament I had many issues with my health, and today was not my day obviously. I was not feeling well," said the Ukrainian in a news conference.

"I hate matches like this. I didn't want to show this kind of game in front of this big crowd, but unfortunately I'm just not able to play now."

"I just woke up today with a viral illness or whatever it is. I don't know. I don't know what happened, but my throat is not well. I'm not breathing well."

"Everything was going well until this morning. I woke up with sickness."

Asked if she considered pulling out of the contest, given her condition, Tsurenko added: "I didn't want to do it because of the crowd and because it's a quarterfinal."

"I took a lot of medication before the match. I think there was nothing else we could do."