The resurgent Kenin, who won the 2020 Australian Open but had to come through qualifying to face the seventh-seeded Gauff, was the more confident of the pair of Americans, dictating play and pushing the teenager around the court at the All England Club.

"Right now I'm very frustrated and disappointed," Gauff said after losing 6-4 4-6 6-2, her first-ever opening-round defeat at the grass-court major.

"So, yeah, I think it makes me want to work even harder. I feel like I have been working hard, but clearly it's not enough. I have to go back to the drawing board and see where I need to improve and how to do the right drills to do that."

Opponents have targeted Gauff's vulnerable forehand and she said she knows that shot needs work.

"Obviously my forehand," she said.

"Being more aggressive on those shots. I think I made too many errors on my forehand and backhand today."

She also needs to do a better job of taking the fight to her opponent, she said.

"I didn't really put too much pressure on her," she said.

"I felt like she could make a ball on the court, didn't have to be as good, and I wouldn't do much with it. That's what happened.

"If I played too passive, she has a game where she can hit aggressive shots."

Kenin, who has been ranked as high as world number four in March 2020 but is now 128th, called 2023 a "comeback year" for her and said she benefited from low expectations on Monday.

"When I was higher ranked and everything, people looked at me like I should win," Kenin said.

"I knew she'd be a bit more nervous because more pressure's on her than me. I just tried to use everything I could this match to my advantage."

Kenin will face China's Wang Xinyu in the second round.