Mighty Murray eases into Masters Cup semis

(CNN) -- British number one Andy Murray booked his place in the Masters Cup semifinals after a comfortable 6-4 6-2 win over Frenchman Gilles Simon in Shanghai on Wednesday.

The world number four, making his first appearance at the season-ending eight-man tournament, followed up his opening win over American Andy Roddick with an impressive display at the Qi Zhong Tennis Stadium.

Murray was quickly into his stride, breaking Simon twice, as he raced into a 4-0 lead.

The world number nine staged a fightback, but the Scot held his nerve to take the opening set.

In the second set Simon managed to hold his opening serve, only to see Murray take the next five games with relative ease.

On match point, the Scot played a deep forehand approach shot that Simon was unable to contend with, enabling him to wrap up the match in one hour and 33 minutes.

"It was one of my best matches in recent months," The Associated Press quoted Murray as saying.

Simon -- who beat defending champion Roger Federer on Monday -- still has a chance to advance from the red group if he wins his final match against world number 27 Radek Stepanek, who was called in to replace the injured Roddick.

Meanwhile, Federer, who needed to beat Stepanek to keep his own hopes of qualification alive, was made to fight hard on his way to a 7-6 6-4 victory.

However, the world number two can still go out of the competition if he loses his final group match against Murray on Friday -- and the Swiss is downbeat about his chances after coming into the event with a back injury and then being struck by the stomach problem following Monday's loss to Simon.

"I woke up and felt terrible -- I couldn't even leave my room. It would have been impossible to play yesterday," said the world No.2.

Federer said he got a lucky break when Roddick pulled out with an ankle injury, joining world number one Rafael Nadal on the sidelines.

"At the end of the day I still have a chance. I hope with a day of recovery, I'll make a miracle happen here and get through into the semis," he said.

In the gold group, Nikolay Davydenko of Russia will face Argentine Juan Martin Del Potro, with the winner assured of a semifinal spot.

Novak Djokovic, who qualified for the last four on Tuesday, meets France's Jo-Wilfried Tsonga, who has been eliminated after losing his first two matches.

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