Jamaal Charles, Nick Collins done for season

Jamaal Charles and Nick Collins are both done for the 2011 season.

The Kansas City Chiefs Chiefs said Monday that they will put running back Jamaal Charles on injured reserve with a left knee injury, meaning he is done for the rest of the season.

Charles was hurt in the first quarter of the Chiefs' 48-3 loss to the Detroit Lions on Sunday. He took an awkward step out of bounds while finishing off a run and immediately grabbed at his knee. Charles had an MRI exam on Monday and Haley said the team decided he would be placed on IR.

Charles was coming off a breakout season in which he ran for 1,467 yards. He and the rest of the Chiefs are off to an awful start, losing their first two games.

Meanwhile, safety Nick Collins is out for the season after injuring his neck in the Green Bay Packers' victory at Carolina on Sunday.

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Packers coach Mike McCarthy says Collins spent the night in the hospital and arrived back in Green Bay Monday afternoon. After meeting with the team's medical staff, they determined his season was over.

The team was not willing to disclose specifics of the injury. McCarthy says it's not clear if he'll need surgery.

Collins has been selected for three straight Pro Bowls.

It's a new season but the same old problem for the Packers, who won the Super Bowl last year despite a rash of season-ending injuries to key players.