Maria Sharapova of Russia reacts after scoring a point against Julia Goerges of Germany during their match at the Pan Pacific Open tennis tournament in Tokyo Sept 28, 2011. [Photo/Agencies]

World number two Maria Sharapova is just happy to be competing at the season-ending WTA Tour Championships this week and is not thinking about her outside chance of usurping Caroline Wozniacki as number one.

The Russian has recovered from the ankle injury she suffered in Tokyo last month and needs to reach the final in Istanbul to have a chance of overtaking the Dane.

"It's tough to talk about (number one) coming off the injury in Tokyo and not even knowing if I'd be able to compete for the rest of the year," Sharapova told reporters on Monday.

"I think I'm just fortunate enough to say that I'm here and I'm going to be competing. That, to me, is a big accomplishment by itself.

"So whether it's number one or number two, whatever it is. I'm very pleased that I made it here and that I have a chance to compete and do well."

The former Wimbledon, US Open and Australian Open champion has won two titles in 2011, cementing her return to the top after a career-threatening shoulder injury almost caused her to quit in 2009.

It will be her fifth appearance in the season-ending event but her first since 2007 and she said she was delighted to be back among the elite.

"It means a lot," she said. "The last couple of years at this time I was sipping a margarita on the beach and now I have another tournament. So I'm quite excited about it."

Wozniacki has won six titles this year and though she has yet to win a grand slam title, she is relishing everything that goes with being top of the pile.

"Of course when you've been number one the whole year, you'd like to finish the last week as number one as well," she said.

"That would mean a lot to me since not a lot of people have finished the year two times in a row as number one."