Murray has now beaten Federer three times in succession
Andy Murray continued his preparation for the new season with an impressive win over Roger Federer in Abu Dhabi.
The British number one came through 4-6 6-2 7-6 (8-6) and will face Rafael Nadal in the final of the exhibition event on Saturday.
Murray beat James Blake in his opening match of 2009 on Thursday, before beating Federer for the fifth time.
"It was great," said Murray after his semi-final win. "Every time you play Roger it's a great challenge."
He will face world number one Nadal after the Spaniard beat Russia's Nikolay Davydenko in straight sets 6-2 6-3.
Murray appeared to struggle with his back in the closing stages but played down any problem afterwards, saying: "I think it's just that I haven't played a match in six or seven weeks. Today was pretty physical, I did a lot of running, so I'm sure it's just a bit stiff."
Federer, playing his first match of the year, looked in the mood to finish things quickly as he opened up an early 3-0 lead with some aggressive tactics.
Murray was soon back on level terms as his scrambling behind the baseline forced errors from the incoming Swiss.
But with a tie-break looming, Murray's concentration slipped as he let a 40-0 lead disappear at 4-5 and a double-fault handed Federer the set.
The second set brought a dramatic shift in momentum as this time Murray took control with three breaks on his way to a 6-2 set, and the Scot raced into a 4-1 lead in the decider.
When the British number one was presented with a smash for 5-1 the match looked to be his, but he missed and Federer roared back with four straight games.
In the end it was Murray who was thankful to make it to a tie-break and he grabbed the first mini-break to change ends at 4-2.
In the big one we played, at the US Open final, he beat me pretty badly
Three match points went begging from 6-3, much to the crowd's delight as Federer kept the drama going, but Murray finally converted at the fourth opportunity when the Swiss made an error.
"We've had a lot of close matches in the past," Murray added.
"I've got the better of him on a few occasions but in the big one we played, at the US Open final, he beat me pretty badly. Hopefully I'll maybe get him in a Slam one day."
Murray will play Nadal in the final before heading to Doha next week and the start of the ATP season.