Fourth seed Jessica Pegula's greater experience proved telling as she beat rising fellow American Iva Jovic 4-6 6-3 6-1 to equal her best Wimbledon run by reaching the quarter-finals for the second time on Sunday.
Pegula dropped her first set of the tournament in a scrappy opener featuring seven service breaks but she raised her level after that against the 18-year-old.
Serving with more authority and cutting out the unforced errors, she won four games in a row after losing the first game of the second set and did not look back.
Jovic, the 16th seed, began to look dispirited in the third set as the 32-year-old Pegula moved quickly towards the finish.
"That was really tough," Pegula, who has made at least the quarter-final stage of all four Grand Slams, said on a sunny Court One.
"Iva's a great player and brings lots of energy and intensity and I just couldn't find my serve in the first set even though I wasn't playing badly.
"Luckily I started to serve better."
Pegula, one of five American women to reach the last 16 for the first time since 2002, could face a compatriot in the last eight if Coco Gauff beats Switzerland's Belinda Bencic later on Sunday.

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