Rafael Nadal produced one of his best performances of the year to beat Andy Murray 6-4, 6-1 at the ATP World Tour Finals and move within sight of the semi-finals on Wednesday.
The 29-year-old 14-time Grand Slam champion looked more like the dominant player of old as he edged a tight first set at the O2 Arena before running away with the match.
With two wins out of two the Spaniard will be assured of one of the top two places in the Ilie Nastase Group if Stanislas Wawrinka beats David Ferrer in the later match.
Murray, who beat Spaniard Ferrer in his opener, faded badly in the second set after Nadal finally broke serve decisively in the 10th game having wasted several earlier opportunities.
Britain's world number two, who has one eye on next week's Davis Cup final in Belgium, looked distracted, surrendering nine points in a row early in the second set, and Nadal needed no second invitation to press home his advantage.
Murray, who bizarrely trimmed his fringe during a changeover in the first set, can still reach the semis by beating Wawrinka in his final round-robin match on Friday.
Resurgent Nadal's late-season form, including finals in Beijing and Basel, have lifted him to fifth in the world rankings, having fallen to 10th during a torrid summer.
In the other Ilie Nastase round robin Group match of the night, fourth ranked Stanislas Wawrinka beat David Ferrer 7-5, 6-2.
Wawrinka battled back from 5-2 down in the opening set to claim the match.
Nadal tops the group following his win over Murray, and the Briton will next face the Swiss for a place in the semi-finals of the ATP major event.
Following his win Wawrinka said: “It was a tough battle. It’s always difficult to play David and I’m really happy. I didn’t start well but I started to find my game. Andy is an amazing player. He’s No2 this year, he’s had an amazing year. He’s always tough to play, especially at home. I’ll look forward to that match.”
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