Right folks, I'm heading off to dream about what I could do with $240,000, but I'll be back with all the build-up to Murray against Federer from 19:30 GMT. I trust you'll be joining me?

Good. It's a date.

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I doubt Ferrer will dwell too long on his disappointment however. He'll head off for an end of season holiday with $240,000 in his back pocket. Stick it all on red?

Just looking at the stats and it was a tale of missed opportunities for Ferrer. Both players had nine break points in the match, with Nishikori taking five and Ferrer only two.

Piers Newbery
BBC Sport at the O2 Arena in London

"The O2 crowd finally got three sets, and more than that they got 41 winners and a performance that will demonstrate to those not too familiar with Nishikori just why he is already among the game's elite. The odds are that he will face Djokovic in the semi-finals, which might be one of the few match-ups that would worry the Serb after his US Open semi-final defeat. For now, the 40 Japanese journalists who took accreditation for the first time might need to call their hotels ahead of the weekend."

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"Almost perfect" hardly does it justice. As Andrew Castle hinted, Kei Nishikori looked a Grand Slam champion in the making in that third set. He seems to have the work ethic and style of Michael Chang, but with an extra dose of power on both sides. A little more work on the serve and we could be looking at a new superstar of the game.

Kei Nishikori: "The third set was almost perfect. I served well and everything worked well in the final set. We've played each other four times this year and always three sets."

On the late change in opponent after Milos Raonic pulled out injured, Nishikori added: "It was really difficult to make this adjustment - they told me one hour before the match, it was tough to change tactics but I'd prepared well and I'm happy to win today."

Andrew Castle
BBC tennis commentator on BBC Two

"Nishikori will be an all-court threat for years to come. He is deadly on a clay court too. At his first World Tour Finals he has won two of his three group matches. Very impressive indeed."

Tim Henman
Former British number one on BBC Two

"I think it's fitting that Nishikori went through. Ferrer came in as a reserve and put in a great performance. He can't have had much notice but the way these guys move, it was really nip and tuck in first two sets. When Nishikori serves consistently he can dictate the points from the back of the court."

That result ensures Roger Federer's place in the semi-finals. Nishikori has one foot in the last four, but could still go out if Murray wins tonight. The Scot must beat Federer in straight sets to go through. Any other outcome and the British number one is out. A single set for Federer means Nishikori is through in place of Murray.

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It's all over. Nishikori breaks again and takes the final game to 30 when Ferrer goes long.

Ferrer still looks pumped for this one. And with reason. He knows he still has a chance on the inconsistent Nishikori serve. A forehand blast is too hot for Nishikori to handle and he nets to give his opponent two break points. They are both saved, followed by two more. And Nishikori finishes off the game with another sumptuous sliced forehand dropshot winner.

Tim Henman
Former British number one on BBC Two

"You can hear and see that David Ferrer still thinks he's got a chance of getting back into this game against Nishikori's serve."

Image source, AFP

Nishikori looks like one heck of a frontrunner. He's gone through all the gears and is now officially in overdrive. To his credit, Ferrer claws back from 0-30 to 30-30 and then from 30-40 to deuce. Two good serves later, he has his first game on the board in the third set.

Vassos Alexander
BBC Sport commentator

"Nishikori's taking this deciding set by the scruff of the neck and he's not letting go."

Not long left now, it seems. Nishikori serves out to love and is now only two games away from victory.

Miles Maclagan
Former coach to Andy Murray and Laura Robson on BBC Radio 5 live sports extra

"Kei Nishikori is on a par with what we saw from Djokovic last night in terms of shot-making. Ferrer just doesn't have those two or three extra gears. He's just exploding into those forehands."

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This match is only heading in one direction now. Ferrer smacks his racquet on the ground in frustration after double faulting to go 0-30 behind and heads to the net for a new one. Nishikori misses a sitter but makes amends with a backhand winner for two break points. He misses the first one by a whisker but hits the slot with a crosscourt backhand to round off the double-break.

Brilliant from Nishikori now. He's keeping the points short and really starting to stick the knife in. At 40-15, however, he plays a rare loose shot and misses a forehand by some distance. It matters not as Nishikori closes out a 2-0 lead.

The boys in the Beeb box know their stuff you know. Nishikori dictates from the first point, and breaks at the first opportunity when a powerful return rushes Ferrer into a backhand, that drifts beyond the baseline.

Who's your money on then? Andrew Castle is backing Nishikori. Tim Henman, eventually, agrees. Here we go, with Ferrer serving.