Unseeded Tomas Berdych created one of the shocks of the season by beating sixth seed Ivan Ljubicic 6-3 6-4 3-6 4-6 6-4 to win the Paris Masters.
The 20-year-old Czech wasted three match points in the deciding set before hitting a backhand winner to seal victory after three hours of tennis.
He had raced into a two-set lead before Croatian Ljubicic hit back.
Ljubicic - who had won 20 of his last 22 matches - is guaranteed a place in the Masters Cup despite the defeat.
Berdych, ranked 50 in the world, had put out former French Open champions Juan Carlos Ferrero and Gaston Gaudio and world number six Guillermo Coria on his way to the final.
"I am very happy because this was my first Masters final and my first win and it was such a great match," he said.
Ljubicic said: "Congratulations to Tomas - he killed us all this week."
The Croatian was full of admiration for the style of Berdych's play and said: "The perfect word to describe him is dangerous. You never know what to expect from him, he can do it all.
"He played really well and there wasn't much I could do. I didn't have many chances, he was just too good."
Berdych showed no signs of nerves early on as he grabbed a break with a sweetly-struck volley to lead 3-1 and went on to take the first set 6-3.
He struck a deft backhand volley to secure a break and go 5-4 ahead in the second set, and won the third of three set points to take a decisive advantage in the match.
Ljubicic then hit back, closing out the third set 6-3 and the fourth 6-4 to level.
To compound his problems, the Czech needed treatment on his left thigh at the changeover ahead of the final set.
But he held on to take the match with a crushing backhand on his fourth match point and claim the biggest title of his fledgling career.