Jose Mourinho talking to Sky Sports: "There are some matches when we feel it's not our day. That applies to football and any other sport. But he can play for pride and he should play for the people who are behind him. He can only give his best. Sometimes a big defeat is the start of many many victories."

Image source, AP

Sadly folks, that means Murray is out of the tournament, with only pride to play for in the remainder of this match. It's the first time Federer has bageled Murray and his first love set defeat for four years.

Murray looks shell-shocked as he pushes another forehand beyond the line then nets to open the door to Federer at 30-30. Two weary backhands and the Swiss has the set.

Federer is being relentless, serving and volleying to go 40-0 up and forcing Murray into errors with deep, heavy groundstrokes. This is an absolute rout. If Federer wins one more game, Murray is out.

Federer unleashes a pearler of a forehand down the line and Murray is starting down the barrel at 0-40. A horrible backhand flies a few yards long and Murray is 4-0 down. If the rot is to be stopped, it has to start now.

Pantomime boos as the TV cameras pick out Chelsea manager Jose Mourinho in the O2 crowd.

Image source, Reuters

Federer serves out to love. Murray hardly touches the ball.

Disastrour start for the British number one. Remember, if he loses this set he is out.

Jeremy Bates
Former British number one on BBC Radio 5 live sports extra

"It's the sign of a great champion here with Roger Federer on the break points. He goes after the forehand, doesn't do anything too rash and draws the error."

This is already engrossing. Federer plays a masterful point, drawing Murray in then lobbing his with a volley. Murray responds with back-to-back aces but then double faults to leave us at deuce. A backhand into the net gives Murray break point, but Federer squanders it with a wild forehand. But two more Murray errors and Federer is a break up.

You're as divided out there in the world of social media as the O2 crowd. Here's some of your early thoughts...

James:, external "Murray has to bring the fire tonight, no point going out with a whimper! Head says Roger, heart says Murray! Come on Andy!"

Srikanth:, external "Just came in after a long day at work! Great way to cap it off. Go Roger!"

John:, external "Federer to win in two with a second set tie break that's as close as Andy Murray will get to him - he doesn't have enough game for an on fire Federer."

Fissuh: , external"Matter of justice I wish Andy win but there is no always justice in sports so let the better win. Intense game. Come on Andy."

Federer misses a easy put-away then nets a forehand, and Murray has half a chance. Federer fights back to 30-30 then is gifted a point when Murray loops a forehand long. A Murray return catches the tape to put Federer 1-0 up.

Jeremy Bates
Former British number one on BBC Radio 5 live sports extra

Image source, Getty Images

"It seems unreal that Federer hasn't got a Grand Slam title this year when you notice he's won 70 matches this season - the highest of any men on tour. He's really put himself out there week in, week out, but hasn't won any of the big ones."

Service warm-ups underway now. This feels big. Seconds out. Round one.

At the toss, Federer looks resplendent in a two-tone knitted cardigan, Murray has his standard faded grey T-shirt on. There's a vaguely comical moment as the coin comes to rest against the net, requiring a re-throw. Federer throws his cardie into the crowd and we're into the warm-ups. I can feel the tension and I'm just watching on the goggle-box.

Image source, Getty Images

You gotta love the razzmatazz at the O2. It's kind of showy but stylish at the same time. Murray walks out first to a big cheer, followed by Federer, who almost raises the roof.

The vote is now closed - thank you for participating.

A significant 66.4% of you DON'T think Murray can beat Federer tonight.

With just 33.6% of you believing Murray can win, Rory, external tweets the evening's rallying cry: "Come on Andy!!!"

Andy Murray: "It's going to be a tough match, a great atmosphere, packed house. I'm looking forward to it. I need to play well, that's very important. I will have to be intense, not give away any game, reduce unforced errors and be aggressive."

Roger Federer: "Andy needs and wants to win this match. I'm aware of that challenge. I have to play my game be aggressive and stick to what's been working these last few weeks and months."

Federer, meanwhile, has been talking up his opponent's chances, saying Murray's confidence will be boosted by his recent upsurge in form.

"I'm sure his belief is higher now again," said six-time champion Federer. "Beating David Ferrer twice, and Marin Cilic as well in Beijing, Jo-Wilfried Tsonga at the US Open - those are the matches he needed to win down the stretch at the end of the season, which he did."

Murray says he's fully prepared to hear members of his supposed home crowd cheering for Federer. "The crowd will probably be more split when I play against Roger but that's no surprise," he wrote in his BBC Sport column.

"I've played him all over the world - in Asia, America, Australia, Canada and Europe, at Wimbledon and three times at the O2 - and pretty much everywhere he goes he gets very good support."

Stewart Mills:, external Going to be an intense battle tonight. Both Murray and the Federer will be desperate to avoid Djokovic in the semis.