Down 0-2 in the second set after winning the first easily. Pegula stormed back to take control of the match and won six games in a row in their fourth-round clash halted once by rain on Monday.
The 28-year-old American won the match 6-3, 6-2 in one hour and 13 minutes to make the quarterfinals for the first time in the US Open.
Pegula capitalised on her solid returns — 27/44 points won on return (61 percent) as compared to Kvitova who claimed 22/53 points (42 percent). She also made fewer unforced errors — 13 as against 24 by Kvitova and won six of the seven break points that ame her way whereas Kvitova could manage to win only two of the six chances she bagged. Though Kvitova had 18 winners as against seven by her American opponent, the 32-year-old from Czech Republic served five double faults to none by Pegula.
Pegula, who had reached the quarterfinals both at the Australian Open and at Roland Garros, lost in the third round at Wimbledon.
Coco Gauff and Caroline Garcia had advanced to their first US Open quarterfinals on Sunday.
–IANS
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