After an exciting battle to the 6,445-foot summit atop Mt. Baldy in California, Team Rabobank's Robert Gesink emerged victorious and in the process also took over the overall race lead from Team Garmin-Barracuda's Dave Zabriskie. Gesink outclimbed two Colombia-Coldeportes riders on his way up the final climb of the day.

25-year-old Gesink, who suffered a serious four-place fracture in his leg in September last year, took the leader's jersey by making up 39 seconds while adding another 46 to his lead going into the final stage in Los Angeles on Sunday.

Zabriskie, who has finished second overall in the 2006, 2007 and 2010 editions of the Amgen Tour of California, slipped into second overall, while his American teammate Tom Danielson climbed from 7th to 3rd overall after today's stage. Team BMC Racing's American Tejay van Garderen entered the day in second place, but lost two places and is out of podium range after Saturday's stage.

"I am very happy to take the stage victory, and of course am very happy with the effort the team put in," Gesink, who finished 6th overall in the 2010 Tour de France while only a 23-year-old, commented and added "We started riding very early because we saw [Chris] Horner in the first group. A guy who does an attack like that has to be a really big rider to make a race as he did today. It was an incredible chase today; everyone was suffering. On the last climb I decided to go with five kilometers left. I think I looked back and the remaining group was small; it worked out perfectly. In the end, I was happy to take the stage victory."

Gesink overtook Jhon Atapuma of Team Colombia-Coldeportes with a little under 1 kilometer to the finish of the stage and crossed the finish line first after a stage that took the cyclists 78.3 miles from Ontario to the top of Mt. Baldy. Atapuma's teammate and fellow Colombian, Fabio Andres Duarte Arevalo, finished third.

Defending Amgen Tour of California champion American Chris Horner of Team RadioShack-Nissan rode alone with Atapuma for more than 20 miles during Saturday's race, but faded in the final three miles to finish in sixth place on the day. Danielson finished in fifth place, moving him to third place overall.

What the stage lacked in distance, it more than made up for in vertical climbs, featuring two brutal climbs at Glendora Ridge Road and Glendora Mountain Road and 15 switchbacks before the finish.

As with yesterday, the attacks started early after the official start of the race. Initially, it was German Jens Voigt of Team RadioShack-Nissan and Dries Devenyns of Omega Pharma-QuickStep that took off in front of a break of about 10 riders, but Devenyns dropped back and Voigt was joined by Michael Matthews of Team Rabobank and Bontrager-Livestrong's Nathan Brown.

About eight kilometers from the first KOM of the day, there was a big group off the front with a one minute, 10 second advantage on the peloton. The group consisted of Voigt, Horner, George Bennett, Gregory Rast - all with Team RadioShack-Nissan; Timothy Duggan of Team Liquigas-Cannondale; Maxime Bouet and Mikael Cherel of AG2R La Mondiale; Marc De Maar and Bradley White of UnitedHealthcare Pro Cycling Team; Atapuma; Alexandre Geniez of Team Argos-Shimano; Lucas Euser of Team Spidertech - powered by C10; Christopher Baldwin of Bissell Pro Cycling; and Brown.

Points for the first KOM competition of the day went, in order, to Bennett, Voigt, Horner and White, and as the riders descended the twisty and technical road, the gap was at one minute, 45 seconds. Team Rabobank, Team Garmin-Barracuda and Omega Pharma-QuickStep were taking turns at the front the group, and the gap held at two minutes. Shortly thereafter, Euser and White dropped from the break, leaving the initial eight riders.

Horner and Atapuma began working alone at the front of the break, while the rest continued to chase or dropped back to the main group. With a three minute, 40 second lead, they continued on as Team BMC Racing worked powerfully at the front the peloton for teammate van Garderen. Atapuma and Horner were the first riders of the second KOM of the day, followed by Duggan and De Maar. With 20 kilometers of the stage left Atapuma and Horner's lead held steady at two minutes, 25 seconds.

The two leaders continued to work together as they headed toward the base of Mt. Baldy one minute, 25 seconds ahead of the nearest chasers. Team BMC Racing continued to push the pace at the front of the peloton. As Atapuma attacked and Horner responded, Gesink moved out in front of the peloton, attempting to catch the race leaders alone. He was followed by Danielson and van Garderen. Gesink and Danielson rode ahead of van Garderen, with Gesink just 35 seconds behind Atapuma.

Moving swiftly up the hill, Gesink dropped Danielson, then caught and passed Horner, but Horner didn't give up easily, hanging onto Gensink's wheel. Meanwhile, Arevalo began moving up, passing van Garderen and charging upwards. With less than one kilometer to go, Gesink passed Atapuma. Atapuma answered the attack, but was no match for Gesink, who crossed the line first.

"It was a very hard day," an exhausted Atapuma commented during the post-stage press conference and added "I got in the break and I was looking at [Chris] Horner when I attacked so I could stay in his wake and contest for a stage win until the last climb. Then I moved away from Horner and couldn't get the stage win. But, for our team to get second and third in a tough stage, and in such an important race, is a very good result anyway."

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