HOUSTON -- Texans Pro Bowl linebacker Brian Cushing is out for the season with a left knee injury that will require surgery.
Cushing was injured in the third quarter of Sunday's loss at Kansas City during a low block by running back Jamaal Charles.
It's the second straight year Cushing has been lost for the season with a left knee injury. He tore the anterior cruciate ligament in the same knee in Week 5 last season.
It's a devastating blow for a team that has lost five games in a row heading into its bye on Sunday.
"I think he was playing at a defensive player of the year-type of level," coach Gary Kubiak said.
"Then here he goes again, he's got to go through this. So I know it's very difficult for him ... (and) I know Cush will do everything he can to get back. But you hate to see anybody go through that especially twice now."
The Texans signed Cushing to a six-year contract worth $55.6 million before this season.
Kubiak said injuries to left tackle Duane Brown (ankle), running back Arian Foster (hamstring) and Ben Tate (ribs) aren't serious.
Tate was injured in the third quarter on Sunday but returned and finished the game.
He told The Associated Press on Monday that he has four broken ribs. He was in a lot of pain, even wincing when he took off his sweatshirt, but said that he expects to be ready to play when Houston hosts Indianapolis on Nov. 3.
"I'll be OK," he said.
Kubiak also said rookies Cierre Wood, Sam Montgomery and Willie Jefferson were released for violating team rules. He wouldn't specify what the players did, but did say it wasn't just one thing.
"I make decisions based on a body of work in everything I do," he said. "I've got five months of work invested with those three young men and I made a decision today to move forward. We've got some things we need to address as a football team."
Wood is a running back who was third on the depth chart after making the team as an undrafted free agent.
With Foster and Tate both banged up, the Texans will need to add depth at that position with one of the open roster spots. Montgomery, a third-round pick, and Jefferson, who was undrafted, are both linebackers.
"We've got some rebuilding to do inside with some issues and we've got some special teams issues," Kubiak said. "So the moves that we make have got to be special teams-oriented to help (special teams coach) Joe (Marciano)."
Players wouldn't discuss why the three were dismissed from the team, but said they agreed with Kubiak's decision.
"It's a shame," linebacker Brooks Reed said. "But it's for the betterment of the team."
Another issue for the Texans is the health of quarterback Matt Schaub. Schaub struggled this season before missing last week's game with ankle and foot injuries.
Former third-stringer Case Keenum got the start on Sunday in his first NFL game. He performed well for most of the game before a fumble late in the fourth quarter sealed Houston's loss.
Kubiak was cagey when asked if Schaub would start after the bye if he's healthy.
"I've got to sit down and look at our situation and what's going on right now," he said. "Obviously Matt's our starting quarterback, Case played this week because Matt wasn't healthy. Case went in and played extremely well. I'm going to sit down on our bye week and evaluate where we're at as a team and move forward from there."
But he did rave about Keenum's performance against the undefeated Chiefs.
"To go in Kansas City in that environment and that noise and handle the football team the way he handled it I thought was impressive," Kubiak said.