Kvitová made her Grand Slam debut at the 2008 French Open, then ranked No. 93 in the world. She lost in the fourth round to Kaia Kanepi in three sets, having defeated Akiko Morigami, Samantha Stosur and then-world No. 13 Ágnes Szávay en route. Later in the year, she reached the quarter-finals of the 2008 Zurich Open, losing there to Ana Ivanovic; this result catapulted her into the world's top fifty for the first time; she would eventually end the year as world no. 44.[2]
Her Australian Open debut, which followed soon after, ended in a heavy loss at the hands of Victoria Azarenka in the first round.[5][6] This started a procession of three consecutive losses, which continued into Open GDF Suez, and Dubai, before she was able to reach the third round at Indian Wells, losing there to the eventual champion, Vera Zvonareva, in straight sets.[7]
She withdrew from the 2009 French Open due to an ankle injury and lost in the first round of Wimbledon to Maria Kirilenko, those misfortunes conspiring against her to drop to world no. 69 in the rankings.[5] At the US Open, she defeated then-world no. 1 Dinara Safina in the third round in three sets, before losing to eventual semi-finalist Yanina Wickmayer in the fourth round. Kvitová was ranked 71 places lower than Safina at the time.[8] At the Generali Ladies Linz, Kvitová reached her second final of the year, but lost in straight sets to Wickmayer.[9] She ended the year ranked 62nd in the world.
2010: First Grand Slam semifinal and rise up the rankings
To kick off the clay court season, Kvitová upset Vera Zvonareva in the first round in Rome, before losing to Andrea Petkovic in the second round. She then qualified for Madrid the following week, but found herself drawn against top three player Caroline Wozniacki, to whom she lost to in straight sets, in the first round. Her poor clay court season culminated in a first round loss to Sophie Ferguson at the French Open.[14]
Entering Wimbledon later in the year, Kvitová had never won a professional match on grass courts, however, she would defy that record by reaching her first career Grand Slam semi-final at the tournament. Then ranked 62 in the world, she defeated, in order, Sorana Cîrstea, Zheng Jie, Victoria Azarenka, Caroline Wozniacki and Kaia Kanepi before being defeated by world number one, defending and eventual champion Serena Williams in the semi-finals. Her run to the final four guaranteed her a debut in the top 30 in the week starting 5 July 2010.[1]
Following Wimbledon, she failed to reach another top-level quarter-final for the remainder of the year. Including the Wimbledon semi-final loss to Williams, Kvitová endured a six-match losing streak, during which she had five consecutive first-round losses, before ending it by reaching the third round of the US Open (where she was seeded for the first time at a Grand Slam tournament, at 25th), where she lost to defending and eventual champion Kim Clijsters; having led 3–0 in the first set, she lost the next twelve games in a row.[11]
Although Kvitová failed to reach any finals in 2010, she ended the year ranked world no. 34, her first top 40 finish to a season, and was recognised as the WTA Newcomer of the Year.[15]