Venus Williams2667278.7%– Victoria Azarenka1244274.7%– Mary Pierce1425074.0%– Billie Jean King1272484.1%– Steffi Graf2783289.7%– Virginia Wade1224971.3%– Petra Kvitova, the tennis star from the Czech Republic, is 6-feet tall, left-handed and can crush her forehand and serve. She has won Wimbledon twice in her career, the only currently active woman to accomplish that feat besides Venus and Serena Williams, who each won their first two from 2000 to 2003. At the moment, Kvitova is ranked No. 6 in the world, and was once ranked No. 2. The week before this year’s Australian Open began, she won the Sydney International by thumping four players, including three-time Slam champion Angelique Kerber, and beating the relentless Ashleigh Barty in a three-set final.Oh, one more thing: There’s good reason to believe she won’t last long in this month’s Australian Open. Of all the women with at least two major titles since 1968, when the Open Era began, none have lost as often, on average, at Slams as Kvitova, the master of disaster.On Monday in Melbourne, Kvitova had an unusual performance: She easily won her first round match by beating Magdalena Rybarikova in straight sets, 6-3, 6-2. Kvitova looked a bit shaky in the first set, when she lost her serve twice and landed just 45 percent of her first serves. But she was much cleaner in the second set, and now — maybe — she can relax and have a strong tournament. She also could improve her winning percentage at majors, which was 70.2 percent at the start of the tournament, the lowest figure among the two-or-better Slam winners in the women’s Open Era. Svetlana Kuznetsova1526171.4%– Chris Evert2993789.0%– Amelie Mauresmo1314375.3%– Justine Henin1412883.4%– Hana Mandlikova1424078.0%– Lindsay Davenport1985179.5%– Monica Seles1803185.3%– Evonne Goolagong Cawley1292782.7%– Jennifer Capriati1404077.8%– Kim Clijsters1323181.0%– Serena Williams3314588.0%– Martina Navratilova3064986.2%– Martina Hingis1533282.7%– Maria Sharapova1944979.8%– Margaret Court961090.6%– Kvitova’s Slam performances are the worst of her peersWinners of multiple Grand Slams by Grand Slam record, 1968-2018* Petra Kvitova923970.2%– *Excluding this year’s Australian OpenSource: WTA Garbine Muguruza602273.2%– Arantxa Sanchez Vicario2105479.5%– Angelique Kerber984170.5%– Tracy Austin611580.3%– Li Na903174.4%– PlayerWinsLosesWin% There are seven other active women who, like Kvitova, have won at least two major titles. All of them have won more of their matches at Slams (Kerber, who had 10 first-round major losses in her first five years on the tour, is still ahead of Kvitova with 70.5 percent). Since Kvitova’s second Slam victory, she has gone no further than the quarterfinals at a major. She has only done that twice, both times at the U.S. Open, in 2015 and 2017. In the rest of her majors she has not gotten past the fourth round. In her career, Kvitova has lost in the first round of a Slam nine times. Serena Williams, who has won 23 majors, is 331-45 at Slams (88 percent) and has lost in the first round only once.Two of Kvitova’s first-round losses occurred last year, in the Australian Open and Wimbledon, the best tournament for her game. (At Wimbledon, she lost to Aliaksandra Sasnovich 6-0 in the third set of their match. Sasnovich had never gone past the third round of a Slam.)So how can a player with so much talent, and so much power, end up looking timid and uncertain? After a promising career start, Kvitova approaches the early rounds of Slams as calmly as when parachuting from an airplane. “When I was younger, I played better on the Grand Slams than the other tournaments,” she said after losing in the first round of Wimbledon last year. “Now is the time when I’m playing better on the other tournaments.” Asked more about the defeat, she said: “The nerves were there again.”Worries at the beginning of a Grand Slam tournament are not uncommon — even Roger Federer, who has won 20, has spoken about being nervous in the first round. But the best players in the world usually overcome that.Some of Kvitova’s more recent woes could be due to the time she was attacked at home by a man with a knife in December of 2016. She didn’t return to the game until the 2017 French Open, which she lost in the second round (she had the same result at Wimbledon). But later that year at the U.S. Open, she reached the quarterfinals, her best result since 2015.Kvitova still has time to cure her Grand Slam disease. She is 28 years old and a natural on the grass of Wimbledon, despite her first-round loss there last year. At the Australian Open, she has an excellent draw, facing unranked players until the fourth round. Her opponent in that round could be Aryna Sabalenka, an up-and-coming 20-year-old who was beaten in straight sets by Kvitova in the Sydney International. Sabalenka is seeded No. 11.Even if Kvitova never improves her Slam winning percentage and finishes her career in last place, well, someone has to be there. She could just call herself the most unpredictable multi-Slam winner in women’s tennis history — not ideal, but definitely unique.