Geraint Thomas will wear the leader's yellow jersey at the Tour de France on Sunday after taking a surprise victory on Saturday's opening stage in Dusseldorf.
In wet, windy and difficult conditions, Thomas won the 14km time-trial as German hope and four-time world champion Tony Martin could finish only fourth.
Reigning Tour champion and Thomas's Sky team leader Chris Froome finished sixth but gained time on his main overall rivals.
Swiss Stefan Kung was second, five seconds off Thomas, whose Sky team-mate Vasil Kiryienka, the 2015 world champion, was third at 7sec.
Organisers had hoped that local hero Martin would become the first German to win an opening stage of the Tour in Germany.
And while he was leading by a second at the only time check 8.1km into the stage, he could not maintain that pace to the end as the wind picked up for some of the later starters.
Thomas was only fifth-fastest at the time check, albeit just four seconds off the pace, but produced a storming run-in to snatch the yellow jersey for the first time in his career.
But it was a miserable day for Spaniard Alejandro Valverde, third overall two years ago, who quit the race after a heavy crash.
He was meant to be a key help for overall contender Nairo Quintana in the mountains and his departure is a huge blow to the Colombian.
Quintana and other potential winners like Australia's Richie Porte and twice former champion Alberto Contador lost more than 30 seconds to Froome.