SAN JOSE (Reuters) - Unseeded Uzbek Denis Istomin upset American Andy Roddick 6-2 6-4 to book a place in the last four of the San Jose Open on Friday.

Hampered by an ankle injury suffered on Wednesday, Roddick, ranked 17th in the world, was second best against his 61st ranked opponent and fell to defeat inside 76 minutes on the indoor hard court.

"He played better than I did in every aspect. He played well," Roddick told reporters. "I was hoping to be able to serve my way into it. That didn't work. From there, it was tough."

Defending champion Milos Raonic of Canada advanced to the semi-finals after he dispatched South African Kevin Anderson 7-5 7-6 in a battle of big servers.

"Obviously, my job was to take care of my serve. That's the most important thing," Raonic, who had 16 aces in the match, told reporters.

"If you fall behind, it's easy for him to close out the set. It's a straining match, but at the same time you just have to be patient."

Nineteen year-old American Ryan Harrison defeated Bulgarian qualifier Dimitar Kutrovsky 6-1 6-4 and will face Raonic for a place in the final.

(Reporting by Mike Mouat in Windsor, Ontario. Editing by Patrick Johnston. To query or comment on this story email sportsfeedback@thomsonreuters.com)