NASHVILLE, Tenn. — The Tennessee offensive line is what coach Mike Munchak calls a "work in progress" now that right tackle David Stewart is the third starter lost to injury.

Center Eugene Amano tore his right triceps in August, and right guard Leroy Harris' season ended in November with an injured right knee. Then Stewart broke his right leg on the team's third offensive play in their 24-10 loss to Houston on Sunday.

Those are not all the injuries on the line.

Munchak said Monday they were waiting for test results on left guard Steve Hutchinson's right knee, but will need to add more offensive linemen. When left tackle Michael Roos hurt his knee and came out for a play, Hutchinson returned with the rest of the line scrambled as the Titans (4-8) lost their second straight and fourth in five games.

"It seems like this is one of those years where everything what can go wrong has gone wrong, and we've been challenged in a lot of different ways," Munchak said.

When Roos hurt his knee with 9:13 left in the third quarter, that jumbled the line with no other linemen available. Mike Otto, who had replaced Stewart, moved to left tackle. Center Fernando Velasco, who hadn't played tackle since high school, moved to right tackle, with Hutchinson coming back at left guard and Kevin Matthews sliding to center.

"It seemed like I was the only one standing and everybody else just kind of fell out," right guard Deuce Lutui said. "At the time, you just kind of wonder who's coming in and if I even have to make a move."

With Stewart out, the Texans batted down even more passes. All the injuries led to Jake Locker being sacked six times and hit a total of eight times, leading him to lose two fumbles and three interceptions. Locker had been sacked only five times in his previous six starts.

"You never want to see your quarterback take a beating like that," Velasco said. "That's our job as offensive linemen. I know it comes with running backs and tight ends and all, but as an offensive line, that's what we take to heart not to let our quarterback get hit like that and to protect our quarterback. ... We didn't do a very good job at it."

Both Munchak and Velasco took issue with a hit the center took from Texans defensive lineman Antonio Smith on the Titans' final offensive play, their sixth and final turnover. Officials flagged Smith for a personal foul, and Locker took up for his lineman by confronting Smith. Velasco called it "very, very cheap shot" and that he hopes the NFL fines Smith, while Munchak was stronger.

"Totally unnecessary. Uncalled for. No place in the game for it. All those things," said Munchak, himself a Hall of Fame offensive lineman. "They threw the flag. Obviously they saw it. I'm sure there'll be some consequences to that. That's just totally out of line."

Now the Titans (4-8), who visit Indianapolis (8-4) on Sunday, have to wait and see if Hutchinson can play before figuring out who starts on the offensive line. Munchak said the veteran might play or could miss a game or two. They also have to correct issues that included at least six dropped passes.

The Titans are another loss away from their second losing season in three years. Munchak led them to a 9-7 record in his first year, and finishing this stretch strong may be a bigger challenge than starting cold as a head coach coming off a lockout, as he did in 2011.

He said the best compliments he got as a player came in seasons with only a handful of wins. Munchak insists nobody will be quitting with future jobs on the line and wants to finish strong.

"You hope if you have to go through a season like this like we're going right now, you hope that you can look back and say there was some good that came out of this. For us right now all you can look at, you've got four weeks left. The goal is to be a lot better in four weeks than you are right now. I mean that's all you can work on. We can't take back the past," Munchak said.

"The question is again can we win all four? We'll see."

NOTES: Munchak also said safety Robert Johnson may be done for the season after tearing ligaments in his foot. DE Kamerion Wimbley was having tests after hurting a big toe late against Houston. WR Damian Williams also hurt a hamstring when he tried to pull up and avoid hitting a stadium worker on the sideline late in the first half.