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By David Ornstein
*Federer 1-0 Murray
Murray gets his first service game off to a poor start when he frames the ball out of the court (it cannons into the overhead scoreboard). The Scot, dressed in blue top, matching shorts and white trainers, sends down a double fault, goes wide and then nets to hand Federer an immediate break of serve. Dreadful start from Murray. Federer playing with bucket-loads of aggression.
** Denotes next to serve.*2058: Hold on to your hats. We’re under way!
2057: As Caroline reports, both players receive a huge ovation. This is comfortably the best pre-match atmosphere we’ve had all week. The 17,500 spectators inside the Arena know this is huge. Federer wins the toss and elects to receive.
Annabel Croft on BBC Radio 5 live sports extra: "I would go out of my way to see this guy (Federer) play and I hope he continues to play for a long while yet."BBC Sport’s Caroline Cheese Tweeting from the O2 Arena:](http://twitter.com/carolinecheese)“Whoah. Big cheer for Murray. But massive roar for Fed. Where’s the partisan crowd Cracking atmos tho.” 2050: And here’s what world number four Murray has to say: "He’s the greatest player of all time. I’ve played well against him in the past so I’ll try to do the same again. I’ll play to win tonight and we’ll see what happens."2048: Some pre-match thoughts from 15-time Grand Slam champion Federer: "It’s always special when the top guys play each other, especially at the ATP Tour finals because you play each other earlier than at other tournaments. We’ve had some great matches over the years so we’ll see how this finishes. I’ve got to be aggressive. The surface is slow and the most attacking player will probably win."2046: This match is being screened live on BBC 3 and streamed here on the BBC Sport website. You can listen to it on BBC Radio 5 live sports extra and, needless to say, receive live updates right here.2042: Murray knocked Federer out of last year’s end-of-season tournament in Shanghai and another victory today would guarantee the British number one and world number four a place in the semi-finals. A win for Federer would do the world number one a world of good but he may still have some work to do to reach the last four.Andy Murray on Twitter:](http://twitter.com/andy_murray)“Chilling in the locker room. See you all in a bit.” 2037: On an occasion like this, I can but urge you to play your part in the action by text to 81111,**606](http://www.bbc.co.uk/dna/606/A59930760)orTwitter**](http://twitter.com/davidornstein)2035: Federer and Murray have met nine times in the past. Murray has won six and Federer thee; Murray four of the past five and Federer the most recent match in Cincinnati in August.2032: Forget about the Champions League football - unless, of course, you want to readJonathan Stevenson’s superb text commentary](http://www.paklinks.com/sport2/low/football/8377430.stm)- because tonight is all about the tennis.2030: The waiting is over. It needs no introduction. Roger Federer against Andy Murray in the ATP World Tour Finals at London’s O2 Arena. Can you think of a more enjoyable way to spend your Tuesday evening