The match, won by goals from Marco Bode and Miroslav Klose, was a bitter, bad-tempered affair, with frequent bust-ups between players and blighted by 16 yellow cards and two reds.
And Schafer blamed the first of the reds, to Germany's Carsten Ramelow shortly before the end of the first half, for disrupting the Indomitable Lions' game plan.
"The decisive
moment of the match was when Ramelow got a red card," Schafer said.
"I'd have
preferred it if he'd stayed on the field and (Salomon) Olembe
had scored."
Olembe was guilty of wasting what seemed a certain opportunity early on, shooting straight at goalkeeper Oliver Khan when put clean through with no offside flag.
But after the break Germany were never made to look like they were a man short.
And after Bode's opener Cameroon themselves were reduced to 10 men, when substitute Patrick Suffo was dismissed for two yellow cards a mere 14 minutes after coming on a substitute.
"We played too much through the middle in the second half
against the 10 men," Schafer conceded.
"We lost possession and that's how they
scored the first goal."