Tennis: Murray in cautious mood

Andy Murray has played down his chances of beating a player he has not lost a set to since January.

The fact his opponent in the Barclays ATP World Tour Finals in London today is Roger Federer also explains the British No 1's caution.

The 23-year-old said: "Every time you play against him it's tough. It's obviously good to win against him. But in tennis every match is completely different. It's a new day. I played great (yesterday), I could play horrible on Tuesday.

"So I need to make sure I practice well to give myself the best chance to play well.

"If I do that, I'll have a chance of winning."

Novak Djokovic turned the tables on Tomas Berdych in London yesterday with a comfortable 6-3 6-3 victory in his opening Group A match at the O2 Arena.

The last time this pair met in the capital was in the Wimbledon semi-finals this summer, when Berdych eased to a straight-sets triumph before losing to Rafael Nadal in his first grand slam final.