KANSAS CITY, Mo. (AP) Chiefs running back Jamaal Charles will miss the remainder of the season with a torn ACL in his right knee.
The star running back hurt his knee in the third quarter of Sunday's loss to Chicago. An MRI on Monday confirmed the tear.
Earlier Monday, coach Andy Reid said ''the worst case is the ACL is torn. That's probably the direction it's heading.''
Charles was making a cut deep in Bears territory on Sunday when his right knee buckled at a gruesome angle. The four-time Pro Bowl selection needed help from a trainer and linebacker Justin Houston to get off the field, never once putting any weight on the leg.
Charles tore the ACL in his other knee four years ago, missing most of the season.
''I talked to Jamaal yesterday and he was obviously down,'' Reid said before learning the diagnosis, ''but he is positive about coming back, getting himself back. That's where his energy will be directed, getting through the surgery and getting back to where he can play.''
Charles could have enough time to get back next season. While the injury typically sidelines a player for about a year, Vikings running back Adrian Peterson beat that timeline by several months. Peterson tore his ACL and MCL on Christmas Eve in 2011, but was back for Week 1 the following season.
Reid sounded optimistic that Charles would make it back eventually.
''He's an amazing guy that way,'' Reid said. ''He's one of those rare athletes that you have an opportunity to coach. They're genetically and mentally strong, and they can do things most people can't do when it comes to their profession.''
That is part of the problem facing the Chiefs: How do they replace one of the best running backs in the NFL, not to mention the most dynamic playmaker on their struggling offense?
Reid said the Chiefs would split carries between backups Knile Davis and Charcandrick West, and wide receiver De'Anthony Thomas has experience at running back. The Chiefs (1-4) also have Spencer Ware, a fullback-running back combo, available on the practice squad.
Among those available outside the organization are former Texans running back Ben Tate and Ray Rice, though it appears the Chiefs have no interest in the controversial ex-Ravens star.
''We'll look in-house before we go there,'' Reid said.
Davis hasn't played much this season while ceding time to West, but he has played well in the past when Charles has been out. He had back-to-back 100-yard rushing games early last season, and played well when Charles was hurt in a playoff game in Indianapolis two years ago.
Davis is a downhill runner, while West offers an elusive change of pace. The former undrafted free agent out of Abilene Christian ran for 31 yards in Sunday's 18-17 loss to the Bears.
''They told us, me and Knile, that we're both going to play. We both have to be ready to step up,'' West said. ''We knew our big brother went down, so it's time to step up.''
It's not just the fill-in running backs that need to step up, though. The Chiefs struggled when Charles went down, unable to move the ball through the air as much as the ground.
Alex Smith was just 16 of 30 for 181 yards in another dismal performance. He was also sacked three times, raising his league-leading total to 22 sacks in just five games.
''It's not fun to be out there playing like that. We know we're so much better than that,'' Smith said. ''For me, there are two choices: I mean, yeah, you can let this get to you. We have a lot of football left. You can get sidetracked, you can get distracted, you can make excuses. Or we can all look internally, we can all stay together and we can fight.''
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