No praise is too high for Andy Murray; no plaudits too many for Roger Federer. At the end of a three hour and a minute match that mattered to Murray only because he made it matter, the British No 1 will play in the semi finals of the Masters Cup and Federer will be on his way home, a season of so much intrigue ended by a player aiming to be another of those who wants to become the world No 1, as he once was.

Murray beat Federer 4-6, 7-6, 7-5, on his eighth match point, when the Swiss, now at No 2, dragged a final, tired forehand out of court and only then would he contemplate the bitter flavour of defeat. Now the Scot has 19 hours in which to get his body and mind into some sort of shape to face Nikolay Davydenko, the Russian who just happens to look as bright and perky as anyone else in this championship.

Remember this - Murray did not have to beat Federer; a defeat would not have meant a jot of difference to him, in only that he does not contemplate losing, that a victory for Federer would have meant the US Open champion remained in the cup and Murray would have been preparing to play Novak Djokovic, not Davydenko on Saturday evening here.

At the match's remarkable climax, only the Wimbledon final between Federer and Rafael Nadal remained brighter or more significant in the memory than this. Its ebb and flow, its twists and turns, its changes of emphasis and command, the ability of both players to command themselves to play majestically when a little less than majestic would have suited most people, meant that you had to pinch yourself constantly to be reminded that it was a round robin. Each point was played like a championship point.

Federer had said beforehand he hoped he might be able to make a miracle happen and win. It was beyond him, but only because Murray is currently quite enjoying making his own little miracles. Federer had arrived before anyone else here, he had spent a couple of days resting, trying to fix his aching back and then suffered an upset stomach after his defeat on Monday to Gilles Simon (the Frenchman's stirring debut in the Masters Cup is also rewarded with a semi final spot).

Murray did not look the epitome of good health after his first match either, the toll of flying from west to east, and consequent jet lag conspiring against finding his best tennis until he recovered the full use of his legs. They were back against Federer but how much is left in the tank to face Dayvdenko, whose ball-striking against Juan Martin Del Potro on Thursday was spectacularly good?

There were so many clutch points, too many to describe in detail. When Federer broke to love in the tenth game of the first set, the impetus was his, but Murray's response was to steal a break in the first game of the second and surge into a 5-2 lead, at which stage the Scot had two set points, on the first of which he missed a backhand, the second with a lob. Federer broke there and did so again on his fourth opportunity in the tenth game. 5-5. Then Murray, from 3-3 in the tie-break, won four consecutive points, one of which, with a backhand stop volley, will long be remembered.

Federer's back was aching now, he was face down, having his muscle manipulated. At 3-0 he looked resigned, he sat in a linesman's chair to draw breath, but spurred himself to life, chasing down drop shots, hitting out with abandon, unnerving Murray, to lead 4-3. It took real resolve from Murray to break back, forcing Federer to hit a smash well out of court on a third break point but only because he was able to toss up an improbable forehand lob when apparently out of court.

Serving to stay in the match, in a game of nine deuces, Federer saved seven match points, two of them with aces. Murray, not fazed, served out to 15; Federer's legs seemed to stiffen. He was lifeless. An eighth match point proved the final as he spun the last forehand we will see from him this year out of court.

Murray is two matches from being the absolute Master - and $1,340,000 richer. Who would dare say he cannot do it?