Maria Sharapova has warned Serena Williams that she is relishing the chance to end her old rival's reign as Wimbledon champion.

Sharapova and Williams will face off for the first time at Wimbledon since the Russian scored a shock victory over Serena in the 2004 final.

Then just a 17-year-old with little experience at the highest level, Sharapova created one of the biggest shocks in Wimbledon history by ending Serena's two-year run as women's champion with a stunning 6-1, 6-4 win.

It was her first grand slam title and, although she has since won at the Australian and US Opens, she has never been back to the final at the All England Club.

But, after an injury-hit 18 months marred by surgery on a shoulder problem, Sharapova is finally approaching something like her best form again and she can't wait to tackle top seed Serena in the fourth round today.

"That's what I thrive on," she said.

"I love going on the court and playing someone that's obviously the favourite to win the match.

"I absolutely love it. She's the defending champion, she's great on this surface and she's won numerous grand slams.

"If there's a challenge ahead of you, it's definitely playing against her, and I enjoy that."

Although Sharapova has been in better form of late, she is well aware that Serena has been in an even more dominant mood - dropping just 10 games in her first three matches.

The 23-year-old also knows that Serena, who has taken the first set of each of her matches by a resounding 6-0, holds a 5-2 career edge in their head-to-head meetings.

"I'd only call it a rivalry when I win a few more against her. I've lost the last few," Sharapova added.

"We certainly had a good rivalry building up but we haven't played for a while."

Worryingly for Sharapova, there is no chance of Serena underestimating the Russian.

In fact, Serena was so angry with herself for playing below 100 per cent in the second set of her third-round win over Dominika Cibulkova, on Saturday, that she vowed to redouble her intensity in the second week.

"I just kind of came off the gas a little too much and you just can't do that in big grand slams like this," Serena said.

"I definitely have to pick up and play better. You always have to be ready. She's obv-iously really good, especially on grass.

"It's really intense (against Sharapova). I think she really knows my game. I think she really studies it.

"It's a great match-up. It's always good to see someone that's a champion out on the court."

Like Sharapova, Serena doesn't believe the 2004 final will have much bearing on this meeting, although she is keen to forget all about that encounter.

"I just remember I was really nervous. I think I put too much pressure on myself. It didn't work out. That was that," Serena added.