Ullrich accepted his positive test for an amphetamine but denies illegally trying to boost his performance.

The German, who won cycling's biggest prize in 1997, said he took the pills during a night out with friends to alleviate depression during his rehabilitation from a knee injury.

But team boss Godefroot said he did not understand Ullrich's actions.

"I cannot understand how Jan, who was in rehabilitation, can find himself in a disco at three in the morning," Godefroot said.

"I cannot understand that to fight an understandable sadness he can be as foolish as to take pills.

"Two months ago, Jan drove into bikes while drunk driving after coming out of a disco and he had pledged this was a first and last time.

"The second time came too quickly. I'm no baby sitter but I have demanded that a report on Jan's behaviour be on my desk every week.

"I want to know everything about his activities and his form."

Ullrich, who pulled out of this year's Tour de France after surgery in May, could now face the sack from the Deutsche Telekom team.

Godefroot added at a news conference: "I did not like his coldness and his lack of doubts.

"Not once did he seem to believe he had to prove he deserved his place back in the team.

"He seemed to take it for granted and I personally feel that it's not."

Ullrich claimed his latest misdemeanour was a misjudgement but not an attempt to enhance his performance.

He said: "For me it is not at all doping and in all the years of my whole career I have never tried banned substances to improve my performance.

"It was a stupidity. It was just a big mistake."