EAST LANSING, Mich. -- Michigan State quarterback Jeff Smoker apologized Thursday for the substance abuse problems that led to his suspension, and he shouldered some of the blame for the firing of coach Bobby Williams.

Smoker was suspended indefinitely on Oct. 24 for violating team rules, and 10 days later his family announced he was seeking treatment for abuse of an unspecified substance.

Smoker, who said he did not fail a drug test, said he was suspended when he told Williams he had a substance-abuse problem and needed help. He said he entered an "intensive'' inpatient treatment program and will continue to be treated for his problem for at least a few more months.

"It wasn't just one substance, and I don't believe that saying the specific substance is the issue,'' he said in his first public comments since the suspension. "But I did abuse them, and it really did affect me.''

Smoker's absence only accelerated Michigan State's deterioration on the field. The Spartans (4-6, 2-4 Big Ten) were ranked 15th after a 2-0 start, but they lost six of their next seven games.

"I understand that I not only affected myself, but many other people through this situation,'' Smoker said.

Williams was fired Nov. 4, two days after a 49-3 loss to Michigan -- the Spartan's most lopsided defeat since 1947.

"I feel that there's a lot of people on the team and a lot of people on the staff that feel responsible for it,'' Smoker said. "And yes, I am one of them who feels partly responsible for it. I feel real bad about what happened to Coach Williams.''

Smoker, a junior, hopes Michigan State's next coach will drop his indefinite suspension.

"I'm willing to do whatever it takes to become a Spartan again,'' he said.

Smoker was struggling with his accuracy before the suspension. In seven games, he threw 13 touchdown passes and 10 interceptions; the previous season, he led the Big Ten in passing efficiency with 21 TDs and eight interceptions.

Smoker said he was not under the influence of drugs during games, but that his substance-abuse problem hindered everything.

"It was just the downward spiral of my life,'' he said. "Not only my play on the football field, but it was affecting everything else. It was affecting my relationships. It was affecting my schoolwork, my personality. I was becoming someone different. It was one of hardest things to realize what was happening, but it was something I had to do.''

When Smoker's 16-minute news conference was over, he let out a huge sigh, hugged team physician Dr. Randy Pearson and walked away from a group of reporters.

"Our family is behind Jeff in his recovery,'' his mother, Sue Smoker, said from her Pennsylvania home. "We will do anything and everything we can to help him.''