Throughout training camp, the Chiefs protected Jamaal Charles by limiting his practice time and closely monitoring his surgically-repaired knee.

The training wheels come off on Sunday when the Chiefs open the season against Atlanta, which will mark Charles' first action in a regular season game since tearing his ACL in Week 2 last season. 

"Whatever it is, I'm not backing down from any situation," Charles told the Kansas City Star when asked how many carries he could handle on Sunday. "I'm here and I’m not going [anywhere]. I've been in every preseason game this year. That tells you a lot right there.

"I'm worried about the Falcons. I'm not worried about my knee. The only thing I'm worried about is staying healthy the whole season."

When the Chiefs released their new depth chart this week, they had two places for running back with both Charles and Peyton Hillis listed as starters. Hillis was brought in as a complement to Charles and to serve as insurance in case Charles does go down.

"I still look at Jamaal as the starting running back," Hillis said. "He deserves it. He's one of the leaders on this team, and his past play has proved it."

Charles put most concerns about his knee to rest with his performance in the preseason. His burst appeared to be back and he was able to make cuts without any problems.

History has shown that with enough recovery time a running back can be productive in his first year back returning from an ACL tear, and Charles believes he is ready to go.

"I felt great playing in the preseason games, getting a feel, moving around, making the moves I used to make out there," Charles said. "Every week I was trying to get better and better. I'm 11 months right now. I'm not even a year [since] my surgery. So I'm back earlier than some people are."

Injury updates: NT Anthony Toribio (ankle), DE Allen Bailey (ankle) and S Kendrick Lewis (shoulder) did not practice on Wednesday. LB Derrick Johnson (ankle), CB Brandon Flowers (foot) and CB Jalil Brown (groin) practiced but were limited.

Toribio was riding a stationary bike on Wednesday, Josh Looney of KCChiefs.com reported, and has not practiced since injuring his ankle in the third preseason game against Seattle on Aug. 24.

If Toribio is not able to go on Sunday, rookie Dontari Poe will most likely start. Poe has been listed as Toribio's backup since the beginning of training camp.

"I'll be kind of nervous and excited, all of those emotions all in one," Poe said. "I'll have to bundle all of that up and go out there to do what I'm used to doing. I've got to settle down, keep myself calm and do what this defense needs."

Chiefs name captains: The Chiefs named their captains on Wednesday. QB Matt Cassel and G Ryan Lilja represent the offense; LB Derrick Johnson and S Eric Berry are the captains for the defense and punter Dustin Colquitt and WR Terrance Copper were selected special-teams captains.

Follow Chiefs reporter C.J. Moore on Twitter @CBSSportsNFLKC and @cjmoore4.