London, Nov 24 (IANS): Seventh-seeded Czech Tomas Berdych saved one match point in the third-set tiebreak to beat ninth-seeded Serb Janko Tipsarevic, a late replacement for Scot Andy Murray at the Barclays ATP World Tour Finals.

Berdych came through a relentless battle, lasting two hours, 26 minutes, 2-6, 6-3, 7-6(6) at the O2 Arena for his second straight win over Tipsarevic, having beaten him at the Paris Masters two weeks ago.

For Berdych, it was a must-win match Wednesday, having lost his opening match over three sets against World No.1 Novak Djokovic.

Berdych is now 1-1 in Group A, having lost to Djokovic after holding a match point Monday. He will next play fifth seed David Ferrer of Spain Friday.

The Czech, last year's Wimbledon finalist, saved a match point at 5-6 in the deciding tie-break having fought back from a set down.

"They've been two incredible matches, these Serbs make it hard. But I'm really happy that I could finish it today," Sky Sports quoted Berdych as saying.

"That's the best things about this sport - until the last point is over the game is still open."

"It's really nice that so many Czechs have come to see me here. They've really helped me a lot. This is the best tennis crowd in the world."

Tipsarevic, who came in for Murray who pulled out with a groin injury Tuesday, has no one to blame but himself for not cashing in on the golden opportunity by slicing a backhand volley wide when he was on match point.

A second break helped him race 5-1 ahead and although he wobbled serving it out, surviving three break points, he clinched the first set with an ace.

Berdych levelled matters thanks to a crucial break in the eighth game of the second, with the deciding set then proving to be even tighter.

After fighting back from 5-3 down in the breaker, Tipsarevic fluffled his lines with a volley when he looked certain to finish things off. He compounded the miss with a double fault straight afterwards that took his rival to the brink of winning.

"If I have that chance one more time, I would still take that ball early and go to the net and play the volley," said Tipsarevic.

"So I am not honestly at all disappointed because of the way I played on the match point.

"I am (annoyed) about myself that I managed to make my first double fault at six-all in the tiebreak and that I completely managed to put Berdych back in the match. He wasn't playing great at the beginning, maybe because of the influence and lack of confidence that he got from losing to Djokovic with the match point up."

Tipsarevic, who is the first standby to play at the year-end championship since Radek Stepanek in 2008, dropped to a 53-26 match record for the season. He is now 2-9 against top-10 opponents this year. He plays his compatriot Djokovic Friday.