However, Evans regained the overall leader's yellow jersey he lost on Tuesday to Dutchman Niki Terpstra, who could only finish in 114th place, over five minutes behind the stage winner.
Grabsch said it was a relief to have put a win on the board.
"Since I won the world title, I must have raced five or six time-trials, finishing in the first 10," said Grabsch.
"However, I was still awaiting a win.
"They were, though, shorter than this one. This was a good distance for me, indeed it was perfect for me."
Evans was the big winner of the day in terms of contenders for overall victory as 2007 Tour de France champion Alberto Contador lost 37sec to the Australian.
Last year's winner Alejandro Valverde - who faces a worldwide two-year doping ban if cycling's world ruling body the UCI acts upon vital evidence, which has still to be received from the Italian sporting authorities - lost over a minute-and-a-half while Italian rider Ivan Basso was over two minutes adrift.
Evans admitted that he had always thought Grabsch was the favourite to win the stage and conceded Contador's challenge in the mountain stages would be crucial.
"For me, the mountains will be a real examination," said the combative 32-year-old.
"Contador is the man to beat in the mountains, even if one should also be wary of other riders.
"I haven't raced a mountain stage since the Tour of the Basque Country (in April).
"The last time that I climbed Mont Ventoux, I won the stage (Paris-Nice). But it will be another thing with Contador in the race."
Source: AFP Global Edition