Only two years separate them in age, but they seem a generation apart. For much of the past decade, Alberto Contador has been the stage-race cyclist to beat, winning five grand tours, the grueling three-week races, including two in Paris. Chris Froome has been something of a development project, rising from obscurity in his African homeland to super domestique in Europe, twice finishing second in grand tours but never winning.

This year the roles have flipped. After a hugely successful spring season, Froome is now the leader of Sky, the most formidable team in cycling. And when the 100th Tour de France begins Saturday on the narrow, wind-driven roads of Corsica, he will be the man to beat, with Contador expected to lead a pack of 196 other riders in the chase.

“I think the obvious choice is Chris Froome,” said Tejay van Garderen, an American on BMC Racing who is a podium contender. “As of now, nobody has been able to climb with him. He’s going to be a hard guy to beat.”

Froome, 28, has more than just a stretch of four stage-race victories this spring to bolster his front-runner status. A Briton born in Kenya, he proved his mettle in last year’s Tour, finishing second to his teammate Bradley Wiggins. And this year’s 21-stage, 2,115-mile course plays to his strengths as a nimble climber and accomplished time trialist, with four mountaintop finishes and two time trials that are shorter but more hilly than last year’s.