National time trial champion David Zabriske (Garmin-Barracuda) usurped the overall lead from Peter Sagan (Liquigas-Cannondale) Thursday at the Amgen Tour of California with a classy performance during the 29.7km time trial in Bakersfield.

Zabriskie set a winning time of 35:59.21, the full embodiment of his ‘Captain America’ skinsuit, while veteran Jens Voigt (RadioShack-Nissan) was next best just under half a minute back. Tejay van Garderen (BMC) was the best of the climbers, netting third at 34 seconds and moving into second overall.

The general classification is now shaping up with a few surprises in the mix: defending champion Chris Horner (RadioShack-Nissan) had a disasterous time trial, losing 2:50 to Zabriskie, while Levi Leipheimer (Omega Pharma-Quickstep) showed solid form to keep within a reasonable distance of pure climbers at 1:44. Vincenzo Nibali sits at 1:52, while Rory Sutherland is the best of the domestic teams at 1:10.

Overnight general classification leader, Sagan, was always going to be fighting an uphill battle today; the Slovakian crossed the finish line in 52nd place with a time of 39:26.

"I went into today going for it, but it seemed from the start that I didn't feel very good," Sagan said. "There was a point I had to decide to rest up and save my energy for tomorrow, where I will try for another stage win."

Today's stage victory was an important confirmation for the US champion that he is on track form-wise for the defense of that title as well as getting the attention of the Olympic selection committee.

"This was a really good course for me, any course where I don't have to get out of the aero bars is advantageous," Zabriskie said. "It's coming soon when they make the Olympic selection, so I wanted to put in a good performance for that."

Zabriskie now has a prime opportunity to achieve what he and his team haven't before, an overall victory in the Amgen Tour. Should he hold onto his lead through the Mt. Baldy mountain finish, Zabriskie said, "It would be the biggest win of my career, it would be amazing, but it's definitely not easy to come by, [after] getting second that many times. It would be a beautiful thing."

Zabriskie expects that a large group will come to the finish at Big Bear tomorrow, as happened in the race's previous visit, but says the Mt. Baldy finale will be difficult for him. "Baldy is a difficult hill, it's going to be hot and those pitches get steep," he said. However, having himself, Andrew Talansky and Tom Danielson in a high position overall will give Garmin-Barracuda a tactical advantage on other teams who will seek to protect one rider.

"Being in the jersey is a good position to be in and having those guys in striking distance, I think we're in a really good position."

Hot, flat and dry

The course in Bakersfield was another toasty affair, with temperatures again soaring past 100 degrees as the riders headed onto the course for the afternoon test. Maarten Tjallingii (Rabobank) set the fast early time, coming across in 36:51, a time which would hold for 20 minutes until Voigt screamed across the line 29 seconds quicker.

"I took it real relaxed," said Voigt. "Sometimes that's the best way to do it. You're not being stressed at all. After the first two or three kilometres I already saw the first rider ahead of me, I though, OK it took me like 5k to catch that guy, and so I tried to catch the another one as well. I came to the halfway point and I saw 16:09, and I saw again that 16:10 was the best time, and I thought, Oh, I'm the second fastest. And I know I'm good on the way back with a little bit more wind. Of course then I get my diesel engine to work, and I thought, You know what, just go, just throw it out.

"I felt good, but I surprised myself a little bit too. It's makes me happy. It's no big secret that I'm getting a little bit older. So that's a good feeling, you can say, Hey you know what, the age doesn't got me yet."

Van Garderen also had his minute man in sight before the time check, but that minute man was none other than Chris Horner. The BMC rider said his early efforts might have cost him time in the second half of the stage. "I saw I was catching Horner and think I got too excited catching him than gauging my own effort, and I paid the price on the way back. I rallied on the climbs and started putting out some good power, but on the false flat headwind section I was really starting to suffer," he said.

"I wasn't surprised I was caught, I was surprised I was caught so soon," Horner said. "I thought [I would lose] 50 seconds, a minute - I didn't care so much about Dave Zabriskie's time because I thought on Mt. Baldy we can make that time up. For sure I thought Zabriskie would pull massive time out of me but not quite that much.

"I had no rhythm. I don't know where it went wrong. I started off maybe dehydrated, I just felt really bad the whole day. I wasn't good on the rollers [warming up] but I wasn't worried, I thought I'd open up later in the race. but I just never did."

Horner said he knew the course wouldn't suit him, being largely flat, hot and windy, but blamed some of his time loss on his focus on getting light for the climbs. "It seems the lighter I get, the better I climb, but the worse I time trial."

Perhaps Zabriskie's biggest challenge now will come from Robert Gesink (Rabobank) who took fourth on the stage behind Van Garderen and is just 39 seconds off the race lead. The result is a good confirmation that the Dutch rider has returned to his top form following a fractured femur last fall. "It's a good sign, so far so good. I'm feeling good so we'll see how it goes the next few days. So far I'm happy. So I'll sit a bit and relax and see how it will be tomorrow. I don't think tomorrow will be the big day. I think Baldy will be the big day."

Van Garderen thinks that the Rabobank rider will be a tough competitor on the climbs ahead. "Robert Gesink had a good ride and he's going to be difficult to control. He's obviously come back from his injuries on a good level to put out in a performance like that."

He also didn't discount the idea of Zabriskie holding onto yellow all the way through to Los Angeles. "Zabriksie was 5th in the Dauphine when it finished on Mt. Ventoux, it's hit or miss sometimes whether he's motivated or not, but he's motivated right now."

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