Defending champion Andy Murray beat top seed Andy Roddick 7-6, 6-4 on Saturday to reach the final of the San Jose Open.

In a repeat of last year's semi-final, third seed Murray served 14 aces on the way to clinching victory and now plays Ivo Karlovic after the big-serving Croat beat German Benjamin Becker 7-6, 7-5 in the other semi.

Murray broke Roddick in the eighth game of the first set but the American broke back immediately to force a tiebreak.

Roddick had three set points but the 19-year-old Scot saved them all and then clinched the set with a backhand pass.

Murray then broke in the fifth game of the second set and after saving a break point at 4-3, held on to reach his fifth ATP Tour final.

Karlovic, the world number 103, fired down 27 aces against Becker to reach his second career ATP Tour final.

"I was serving really good, that was the key," Karlovic said, after taking his aces tally to 87 for the week. "But I also think in the crucial moments I returned well too."

The Croat, who beat James Blake and Mardy Fish on his way to the last four, grew in confidence in the second set and after breaking in the 11th game, he served out for victory.

Karlovic, who lost to Roddick in his only previous final at Queen's Club in London in 2005, said Murray would be a tough opponent.

"Murray is one of the best returners, so it's going to be very difficult either way, but I am just going to enjoy myself out there. I have nothing to lose."