The 17-year-old initially gave Williams, 37, a scare Wednesday, in the second round of the US Open. But the 23-time major champion prevailed, advancing with a 5-7, 6-3, 6-1 win in one hour, 54 minutes.
Williams, seeded eighth in the draw, has never lost to a teenager at the US Open. Her record in the US Open second round improves to 19-0.
“I survived tonight,” Williams said on court to ESPN.
McNally, who is from the Cincinnati suburb of Madeira, Ohio, was making her US Open main draw debut. Earlier this summer, she won her first WTA doubles title, with 15-year-old Coco Gauff. The duo had won the US Open girls’ doubles title together in 2018. She’s currently ranked 121st in the world, a career best.
“For me, I think it just shows that I’m capable of playing with the best — I got a set off Serena Williams,” McNally said. “Had her close in the second set, too. Had some chances. For me, it just gives me a lot of confidence, shows me that I can compete out on the biggest stages. Just keep my head down, I’m ready to go back to work.”
On Wednesday, McNally did not look at all fazed under the bright lights of Arthur Ashe Stadium, taking the first set after a late break. Williams fought off the teenager in the second set and then went into cruise control, dropping just five points in the third. She won all 12 of her service points in that final set.
Williams finished the match with a forceful forehand winner and pumped her fist. She had 32 winners, including 10 aces, to 28 unforced errors. Williams also won 81% of points on her first serve.
“I want to be able to win matches where I’m not playing my best, play players who are playing great, be able to come through,” Williams said in her post-match press conference. “I need to be tested, I guess. Sounds scripted. Actually, I’d rather not be tested in every match. But that doesn’t happen, so it’s important for me to have those, like, really rough, rowdy matches. That helps a lot.”
A six-time US Open champion, Williams is seeking her first title in New York since 2014 and her first grand slam title since 2017, when she won the Australian Open while pregnant.
Williams will next face the winner between Karolina Muchova and No. 29 seed Hsieh Su-wei.
“I’m alive,” Williams said to ESPN. “I’m still here.”