gauff (1)

AUCKLAND, New Zealand — U.S. Open champion Coco Gauff moved into the semifinals of the Auckland Tennis Classic on Friday with a 6-1, 6-1 win over Varvara Gracheva of France on a rainy quarterfinals day.

The top-seeded player and defending champion needed only 24 minutes to win the first set and took the match in 52 minutes. Gauff hasn’t dropped a set at the tournament and didn’t drop a set in winning the tournament last year.

Rain delayed the start of the match and was threatening at the end. But Gauff rushed to victory with dark clouds gathering, sending down five aces.

“I thought I served really well, probably the best so far at this tournament which is something I was really working on in the off-season.,” Gauff said. “Last year there was a lot more rain so I was glad I was able to finish my match.”

Gauff will play fellow American Emma Navarro in the semifinals. The fourth-seeded Navarro beat Petra Martic of France 6-4, 4-3.

Navarro lost to Martic 6-2, 3-6, 6-3 when the pair met in Cincinnati in August. She turned the tables Friday with an authoritative display, putting 80% of first serves in play and attacking Martic, particularly on her second serve.

“Tennis always keeps us on our toes so you’ve got to be ready for things like rain delays,” Navarro said. I was happy with my performance today, played my most comfortable tennis out here.”

Navarro rushed to a 4-0 lead in the second set before Martic claimed a service break and the match went with serve until Navarro took the match on her third match point.