By John Martin

The New York Times blog

In a match of lopsided statistics and surprising lapses, Petra Kvitova of the Czech Republic defeated Tsvetana Pironkova of Bulgaria, 6-3, 6-7 (5), 6-2, to reach the Wimbledon semifinals for a second successive year."I'm very happy," Kvitova said in a courtside interview. "I started great in the beginning, I don't know what was in my mind, but I'm very happy to have won."

Dominating early, Kvitova, seeded No. 8, had hit 24 winners to Pironkova's single winner by early in the second set, with Pironkova showing none of the finesse and power she displayed in easily defeating Venus Williams the day before.

The crowd applauded happily when Pironkova, seeded 32nd, won her serve to tie the second set at 2-2 as the air of imminent defeat began to subside.

Kvitova was starting to miss, her shots finding the net in alarming numbers. Pironkova took a 3-2 lead by breaking Kvitova's serve. The trajectory of the match seemed to be shifting.

Mystified, the 21-year-old Kvitova looked to the sky with upraised hands when she jammed one backhand into the net and another over the baseline to trail 2-4. The question was whether she could recover sufficiently to close out the match.

The answer was mixed. In one four-shot succession, she drove still one more forehand over the baseline, jammed a crosscourt forehand winner into the backhand court, then another forehand over the line, then another crosscourt forehand winner.

She battled the set to a tiebreaker, where the players traded mini-breaks until Kvitova jammed a forehand into Pironkova's backhand corner to lead 3-1. An unreturnable serve took her to 4-1. Pironkova held onto her wits and navigated three winning points in a row to pull even at 4-4. They jockeyed for the lead, trading successful challenges and unforced errors.

It was 5-5 and nobody could guess that Kvitova would slap two forehands wide to hand Pironkova a set point, then another forehand wide on the other side to yield what seemed like an unbeatable lead.

The crowd erupted in cheers. The match was tied at one set apiece. There would be more tennis to watch.

What they saw was a seesaw final set with Kvitova hitting an alarming number of unforced errors, her shots sailing longer and wider by the minute, but still pulled away. As her unforced errors grew to 24 (Pironkova had 16), Kvitova's margin of winners was still growing, too. She hit 46 winners while Pironkova managed nine.

Finally, 33 minutes into the third set, Pironkova faltered under a barrage of Kvitova winners. She lost her serve despite a vigorous rally which she seemed to dominate before Kvitova chipped an unreachable backhand into a corner.

Serving for the match, Kvitova hit an ace to seal the victory she so nearly squandered.