Kansas City running back Jamaal Charles, who rushed for over 1,400 yards last season and earned his first trip to the Pro Bowl, will likely miss the rest of the 2011 season after suffering a devastating knee injury in the first quarter of the Chiefs' 48-3 loss to the Detroit Lions.

Charles, who had the second most rushing yards in the league last year (1,467) after the Texans' Arian Foster, will have an MRI Monday to confirm the initial diagnosis of a torn left ACL.

I don't know the extent of his injury, but it's a terrible loss for us, for our team, says fellow Chiefs running back Thomas Jones. If Jamaal's gone for the year, guys have to step up.

Charles suffered the injury as he sprinted for the first down and planted his leg on the slippery first down marker while he was pushed out of bounds by Lions defensive back Chris Houston. Charles collided with the Detroit Lions' mascot Roary and immediately hit the ground, clutching his left leg and writhing in pain.

Charles was unable to put any weight onto his left leg, and he was carted off the field.

We'll probably know a lot more on him here in the next 12 hours or so, said Chiefs coach Todd Haley after the game.

Prior to Sunday's loss against the Lions, Kansas City had already lost two key players for the rest of the season to knee injuries. Promising tight end from Iowa Tony Moeaki suffered a torn ACL in the Chiefs' final preseason game, and Eric Berry ruptured his left ACL in the team's opener last week against the Buffalo Bills.

Losing Charles, the 24-year-old Texas running back who rushed for over 1,100 yards each of the last two seasons for Kansas City, is an absolute disaster for the Chiefs.

The season will not be canceled as far as I know, Haley says. What we have to do is we have to stop doing those things that are costing us dearly, and putting us in very difficult positions.

The absences of these three key players has been felt in the team's back-to-back lopsided losses. In Kansas City's first two games of the season, the Chiefs have been outscored 89-10.

The Chiefs needed a great running game to bolster its anemic passing game. Behind quarterback Matt Cassel, the Chiefs are ranked 32nd in the league (out of 32 teams). Kansas City is ranked 8th in the league in rushing yards, but this will likely change given their electrifying Pro Bowl running back is done for the year.

The outlook for last year's 10-win AFC Champs looks bleak. The Chiefs have the third toughest schedule in the league this year, and given the way the team has lost in the last two games, with innumerable turnovers, costly penalties, and ill-advised plays, the team is in danger of losing games as well as coaches.

You can't do certain things and win in the NFL, or even have a chance to win, Haley says. Once again, I will take full responsibility for the performance of our team, and we have to make, clearly, a bunch of changes here in what we're doing.

Jamaal Charles was drafted in the third round of the 2008 NFL Draft by the Kansas City Chiefs as the 73rd overall pick.