American Dave Zabriskie won fifth-stage time trial to seize the overall lead in the Tour of California, taking the yellow jersey from four-stage winner Peter Sagan.
Garmin rider Zabriskie, the US time trial champion, on Thursday won the 29.7-kilometer time trial in 35 minutes and 59 seconds to defeat Germany's Jens Voigt by 23 seconds, with 23-year-old American Tejay Van Garderen third, 34 seconds adrift.
Hot conditions and brisk breezes with a barren landscape accented the stage.
"The biggest factor was probably the heat," Zabriskie said.
"Second is the wind. Thirdly there's not much to look at out there. It works on you mentally. But that's the kind of course I like.
"Definitely the wind was in the face. I knew I had to concentrate a lot and keep the speed."
Zabriskie's total time in the overall standings on 20:29:31 was 34 seconds ahead of Van Garderen with Dutchman Robert Gesink third, 39 seconds back.
Slovakia's Sagan, a Liquigas rider who had swept the prior stages to open a 16-second edge when the day began, was 52nd in the stage.
Friday's sixth stage will go from Palmdale to the mountain-top finish at Big Bear Lake, and has two major climbs ahead of Saturday's feature climb of Mount Baldy on the penultimate day of the event.