Hard-serving John Isner scored perhaps the upset of the year on Saturday with a 7-6 (7), 3-6, 7-6 (5) victory over top-ranked Novak Djokovic in the BNP Paribas Open semifinals at Indian Wells, Calif.

The 6'9 Isner fired off 20 aces, and had got his serve up to144 mph. He is the first American to beat a world No. 1 since James Blake defeated Roger Federer in the 2008 Beijing Olympics.

The match lasted nearly three hours, and when it was over, Isner threw up arms and took the loud adulation from the crowd that was firmly behind him.

It's something that you don't experience every day, Isner said. I was just trying to take it all in.

It was only the second loss for Djokovic, who lost to Andy Murray in Dubai. It was clear that Djokovic was overwhelmed by Isner's serve.

It's a lot of pressure knowing that somebody serves that well. You need to win your service points, especially when you get to the tiebreak, Djokovic said. But this time I was unlucky. He didn't wait for it, he went for it.

Isner, who turned pro in 2007, will face Federer in the Sunday final after the Swiss star defeated second-ranked Rafael Nadal 6-3, 6-4 in the other semifinal.

Should Isner defeat Federer, he will become the first American to win at Indian Wells since Andre Agassi in 2001.

Here are the highlights from Isner - Djokovic:

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