Five years ago, Petra Kvitova did not think she was good enough to be a professional tennis player.

On Saturday, she gave Maria Sharapova a lesson in power hitting to win her first grand slam title at Wimbledon.

The 21-year-old hails from the small town of Fulnek, in the east of the Czech Republic, and trained at the prestigious Prostejov club, but she certainly does not fit the stereotype of the Eastern European who grew up on a tennis court and was groomed for the top.

Kvitova said: "Until I was nine I was probably the best but then I was third or fourth in my age group. Around 16, 17 I won some championships in the Czech Republic.

"I didn't think I could be a professional because I was practising only after school for an hour or an hour and a half."

The first real indication that she could be one of the best players, not just in her country but in the world, came at Wimbledon last year, where she reached the semi-finals.

Kvitova had never won a match on grass before but she beat Victoria Azarenka and Caroline Wozniacki, and put up a good fight against Serena Williams in the last four.

It was an important moment for the Czech, not just for her belief, but also for what came next. Far from providing a springboard to the top, Kvitova lost in the first round of her next five tournaments.

This season, though, it has been a different story. Kvitova has won four titles, reached two more finals and made at least the fourth round at all the grand slams.

She said: "When I was here in the semi-finals last year, I thought that I had to beat everybody that I played. And I couldn't, so it was tough for me.

"But I've improved already because I won in Brisbane, I played well in Melbourne and then after that as well, so hopefully it will be the same.

"It was a great experience for me last year because I knew that I could beat players from the top ten at grand slams. It was great, but still I had a lot of work to do. I did it and it's the same now."

Kvitova looked shellshocked as she tried to take in her momentous achievement. She insisted the first time she really believed she could win the title was after her semi-final, and fame is something she is not sure she will enjoy.

The 21-year-old said: "It's part of being a tennis player, when I win Wimbledon I have to expect it. I don't think I'm a star, I just want to stay normal. I don't want to change."

With her grand slam breakthrough, Kvitova jumped to the head of a generation of players that also includes world number one Caroline Wozniacki and number four Azarenka.

Women's tennis has been crying out for new names to come through Kvitova did just that, but she was reluctant to herald the dawn of a new era, saying: "It can be, but we know the Williams sisters want to be again the best players in the world, so I don't know."

Sharapova was equally cautious, adding: "There's always going to be a generation, one after the next. Ultimately they're going to step up at one point. It happened to be in this tournament. We'll see whether that continues."

One thing Sharapova has no doubt about, though, is that Kvitova is the stand-out player of her age.

The Russian said: "She's a grand slam champion. She has a tremendous amount of potential and can achieve many great things."