Browns left guard Joel Bitonio was placed on injured reserve Friday, marking another setback amid an array of injuries suffered by the team so far this season.
"It's unfortunate, Joel is one of our best players up there," said head coach Hue Jackson, who added he doubts the third-year player will return this season. "It makes it a little tough, but we'll find a way."
Bitonio suffered a mid-foot sprain in a loss to the Patriots last week but played through the injury.
The Browns also will still be without veteran quarterback Josh McCown, who returned to practice this week following a shoulder/collarbone injury against Baltimore last month, when they travel to Tennessee this weekend.
"As you guys know, we're going to err on the side of caution with our guys before we stick them out there," Jackson said of McCown. "We want to make sure they're healed up. I think he's close, I think he's really close."The Browns elevated quarterback Kevin Hogan to the active roster earlier this week in an effort to add depth at the position. They also parted ways with veteran backup Charlie Whitehurst.
In the team's most recent injury report, Browns cornerback Joe Haden (groin), nickelback Tramon Williams (shoulder), tight end Gary Barnidge (forearm/hip) and defensive lineman Xavier Cooper (shoulder) are all listed as questionable for Sunday.
Jackson said Haden, who missed the team's loss to Miami with a groin strain, "tweaked" the injured area Thursday in practice.
"We'll see where he is. It's tough, but the one thing I do know about Joe is that he wants to be out there with his teammates," Jackson said. "It's difficult but we've got to keep going. If he can't go, then it's next man up. Let's go."
Browns defensive coordinator Ray Horton said he's optimistic the Pro Bowler will play.
"I know that he will do everything he can to get out there," he said. "Joe is a very competitive guy so whatever he will do to help the team, I know he will do to help the team."
Haden, who had ankle surgery in March, has notched two interceptions through five games.
"I think he has played well. He is doing everything we ask him to do," Horton said. "What he has is just a slight something that made him miss a couple days, a couple reps at practice yesterday, and hoping that he plays well."
The Browns earlier this week got good news on the injury front, as quarterback Cody Kessler (chest/ribs) and center Cameron Erving (bruised lung) are set to play against the Titans.
Kessler, who left last week's loss to New England after a big hit in the first quarter, is expected to make his fourth-straight start.
Erving is set to make his first start since the Baltimore game in which he was taken to the hospital afterward as a precaution.