London, Nov 23: Jo-Wilfried Tsonga remains in the hunt for a place in the semifinals of the ATP World Tour Finals after the sixth seed defeated Mardy Fish 7-6(4), 6-1 on Tuesday.
Tsonga, who lost his opening Group B match against Roger Federer, still has to beat Rafael Nadal in his final fixture on Thursday to have a chance of advancing, while Fish faces an early exit from the season finale at London's O2 Arena.
The result also means defending champion Federer will be guaranteed a semifinal spot if he defeats Nadal in their Group B encounter.
With both players beaten in their opening games, this encounter was a battle for tournament survival.
Tsonga started in aggressive mood, earning three break points before finally breaking at the fourth attempt with a brilliant winner on the run.
Fish broke straight back in the next game, only for the American eighth seed to surrender his own serve again to give Tsonga a 2-1 lead.
Tsonga became the first player to hold serve in the next game, but the often-erratic Frenchman crumbled when he served for the set.
Fish had an animated discussion with the umpire between games and letting off some steam seemed to do him good.
He knocked Tsonga out of his stride with a magnificent top spin lob and levelled the score on his second break point when the sixth seed sent a backhand long.
It took a tie-break to decide the set and Tsonga took it with a pair of big serves to take advantage of his mini-break.
The American started with a break in the first game of the second set, but couldn't maintain his momentum and allowed Tsonga to break straight back.
Both players were mixing in far too many unforced errors between their occasional moments of brilliance, but Tsonga produced enough pressure with his ground-strokes to convert on his third break point for a 3-1 lead.
That blow shattered Fish's morale completely and Tsonga broke again before serving out the match.
Meanwhile, World No.3 Andy Murray withdrew from the tournament on Tuesday after failing to recover from a groin injury.
Murray was told he would need up to 10 days off after suffering the injury in practice last week and, although he initially ignored that advice to play David Ferrer in his opening match at the O2 Arena, he decided to pull out.
Murray will be replaced by Janko Tipsarevic in Group A.
“It was one of those things where you kind of hope that things are going to get better, but reality was that wasn't ever going to happen. I woke up this morning still sore. I was just trying to find reasons why I should try to play.
“I couldn't give anywhere near my best. So that's what was disappointing. It would probably do myself more damage by playing than not,” said the Scot.
He said that his main concern was to avoid damaging the groin further before he goes to America to begin his off-season conditioning regime ahead of the Australian Open in January.
“It might seem like it's a long time away but the Australian Open is six, seven weeks away.”
“I could mess up my preparation for that, for the beginning of the year. That off-season is so important for me and has been for the last few years of getting myself in shape,” said Murray.
In the doubles competition, Rohan Bopanna and Aisam-ul-Haq Qureshi lost their second Group B match, falling 7-6(6), 6-3 to second seeds Michael Llodra and Nenad Zimonjic on Tuesday.
The fifth seeds committed as many as seven double faults in the match as compared to just one by their opponents.
Both the pairs broke once each in the first set to take it to the tie-breaker, which Llodra and Zimonjic won.
In the second set, the Franco-Serbian partnership converted two of the five break points to seal the match.