Russian Nikolay Davydenko beat an exhausted Andy Murray 7-5 6-2 to set up a Masters Cup final against world number three Novak Djokovic on Saturday.
Briton Murray, who would have won $1.34 million if he had gone through the tournament undefeated, was clearly feeling the effects of Friday's three-hour epic victory over Roger Federer -- a match he did not need to win to reach the semi-finals.
Davydenko, the world number five, took full advantage to reach his first final in four straight appearances at the season finale and will play the Serbian world number three, who earlier beat Frenchman Gilles Simon 4-6 6-3 7-5.
Australian Open champion Djokovic made 21 errors in losing the opening set but his nerves settled after an early break in the second and he ground out a win after two hours 50 minutes.
"It's a huge success for me to reach the final," said the 21-year-old, who lost all of his matches without winning a set on his Masters Cup debut last year.
"It would be great if I can end up with the title. I didn't have such a great last couple of months of the season."
Defeat ended a fairytale ride for Simon, who won his ticket to the season finale when world number one Rafael Nadal pulled out injured and then beat defending champion Roger Federer in a round-robin match.
"I defeated the number two, I played three sets in three hours against the number three so that'll give me confidence for next year," said the 23-year-old, who will finish the year as world number seven.
Simon said a neck problem that required a medical timeout at the start of the second set had not affected the outcome, even if he looked second best for much of the rest of the match.
Djokovic also sustained an injury to his calf muscle that required attention in the third set but fended off a late fightback to reach his sixth final of the season.
"I had this role of the favorite, and probably it's had some impact on me at the start of the match," said the 21-year-old.
"I wasn't patient enough and made a lot of unforced errors."
Davydenko and Djokovic have met only twice before with the Russian prevailing when the Serbian retired injured from a Davis Cup match earlier this year but losing 7-6 0-6 7-5 in a group match here last Tuesday.