By Paul Majendie
But Roddick, three times a finalist at the world's most famous tournament, was angry with himself after his victory at dusk on Court Number One was greeted with tumultuous cheers.
"The last two sets were real good," he said. "But I got a little complacent. He was the aggressor for the majority of the first two sets," he said.
"I've had a couple of rough matches here and I am happy to be through," the fifth seed said afterwards.
Kohlscheriber, the 29th seed, has a game well suited to grass and the two battled out two tight first sets. The German recovered from 4-5 0-40 in the second to save that game and claim the tie-break on his first set point.
Roddick, who lost his third final to Roger Federer 12 months ago, retained his focus the better and sealed victory with another thunderbolt ace in just under three hours.
As always, Roddick's serve was his most devastating weapon. He served 28 aces to just 13 from the determined German who refused to be bowed by the American's big guns.
But as the sun set over Wimbledon, Roddick finished off in style, thumping down a 137mph ace to clinch a match against Taiwan's Lu Yen-Hsun for a place in the quarter-finals.
British crowds have taken Roddick to their hearts this year, remembering how he fought so hard against Federer before surrendering 16-14 in the last set of an epic final last year.
He acknowledged their cheers, saluting every corner of the court afterwards.
Now he is just hoping that history will repeat itself.
Croatian Goran Ivanisevic is the only man apart from Roddick to have reached three finals in the Open era without winning any of them. He finally won on his fourth attempt in 2001.
(Editing by Miles Evans)