All that stood between the race leading American and an overall victory was 2.5km of road and a surging Froome, but he could not find the extra energy needed to match the 2013 Tour champion on the way to the Modane Valfréjus ski station.
"Every race you go to you want to shoot for the top," van Garderen said post race. "I am certainly happy with second place and I am really happy with how I am stacking up to all of my tour rivals. I think it is a good sign for July. But right now it is hurting a little bit. But sometimes that is a good thing."
Froome finished 18 seconds ahead of a fourth place van Garderen on the stage, to earn the 10 second time bonus that was to be the final margin of victory.
“I wasn't expecting it to be easy to be honest,” van Garderen said. “It was quite hard. Froome played it tactically pretty well. He knows that I'm better keeping the rhythm so he attacked me at the perfect moment.
“It's never a good sign when you start looking around like I did at the end. For a little bit that gap was just agonising that close. I was trying to hold on but when you give Froome five meters it's hard to pull back.
“Chris is a fantastic rider. He's won so much in this sport. He's already won the Tour. He's obviously hard to beat but we've seen this week that he's not unbeatable.
“I need to step up a level and play some tactics. It seemed to be just me against him in this race but we had some other guys in the mix that changed things and there'll be more at the Tour.”