LONDON — Dominant on serve, lighter and more agile on her feet, all in all the familiar force that has made her a four-time Wimbledon champ, Serena Williams Tuesday dismantled last year’s champ, Petra Kvitova, 6-3, 7-5, and now stands but one victory from reaching her seventh final at SW 19.

“It is very difficult,’’ said Kvitova, asked how hard it is to derail Williams when she is in such dominant, unwavering form. “I can’t say it’s impossible . . . because she’s human.’’

Hard to prove a flesh-and-blood case for Williams based on the thrashing she dealt Kvitova, whose game improved over the 84-minute knockout but never quite reached title-defending form. Kvitova rarely challenged Williams’s serve, long the Californian’s greatest asset, and she often had to scramble to avoid losing her own service games to prevent an even shorter stay under the Centre Court’s closed roof.

Williams delivered 13 aces to Kvitova’s three. Williams won 31 of 36 points (86 percent) off her first serve, far better than Kvitova’s 26 of 44 (59 percent). It took Williams just 30 minutes to stash away the first set, then nearly twice that (54 minutes) to win the second, Kvitova able to scramble her way to a set point in the 10th game when Williams fell to 30-40 on serve at 4-5.

But from there, it all caved in on Kvitova in a span of five long London minutes. Williams first slipped out of the break by winning three straight points, underscoring the hold at 5-5 with a short, targeted smash at the net to Kvitova’s midsection. Kvitova then moved to a 30-0 lead in the next game, only to be rendered grass clippings on four straight points, including the end-of-break forehander that she popped directly into the net on an unforced error.

The 6-5 lead banked, Williams closed it in the next game, finishing the day with a 116-miles-per-hour ace, followed by a first serve that Kvitova could not return. End of Kvitova’s reign. Classic Sister Sledgehammer.

“I think that’s just my game, pretty much,” said Williams, the only American left playing singles this fortnight, following the day’s other losses by Mardy Fish and Brian Baker on the men’s side. “I hadn’t been doing that so much in the past [at Wimbledon], so for me it was definitely important to get out there and just be the best that I could be.’’

“This,’’ said Lindsay Davenport, the retired Yank who is here commentating for the BBC, “is levels and levels above what we’ve seen from [Williams].’’

Still the greatest female force in US tennis, the 30-year-old Williams last won here in 2010, her second win in as many years and the fourth of her career. She lost in the finals in 2004 and ‘08. She has won nine other Slam events, but nothing since her last Wimbledon, a series of injuries keeping her off the court much of last year.

Similar to Kvitova, Williams prefers to win off her serve and her overall strength and power, both players a force from the baseline. With a trip to the semis up for grabs, they didn’t change their approach. It became clear early on that Kvitova’s only chance of disrupting Williams might have been to advance more — or at least a little — but she stuck to form and eventually surrendered to repetitive failure.

“Too many balls [shot] right at Serena’’ offered Davenport. “Serena is such a better athlete. And on days she plays well, there’s not much anybody can do.’’

Standing in Williams’s (seeded sixth) way of a seventh trip to the final: the second-seeded Victoria Azarenka.

“She’s playing unbelievable,’’ Williams said of Azarenka. “It’s going to be another match where I have absolutely nothing to lose. I can just go out there and enjoy myself and have fun.’’

All tournament, Williams repeatedly has said she has nothing to lose. But that never has been the Sister Sledgehammer approach, or reality. The British would call her “cheeky’’ for pretending to be here for reasons other than to try to lay waste to the field.

“No one,’’ said BBC commentator John McEnroe, “seems to want it more on a tennis court than Serena or [Jimmy] Connors.’’

As her media session wrapped up, Williams was asked about her many titles and trophies, a treasure trove that has helped her accumulate upward of $40 million in career winnings.

“I really take every tournament seriously,’’ she said, asked to weigh the emphasis of championships vs., say, mere trips to the finals or semifinals. “But at the end of the day, you add up those Grand Slams and it really helps . . . if I lose, I don’t keep the trophy . . . at the end of the day, if you’re not first, you’re last.’’