INDIANAPOLIS (AP) - The Colts are 0-4, Peyton Manning has spent more time in the coaches' booth than on the field and two defensive starters already have season-ending injuries.

Could this start get any worse? Yes.

After Monday night's 24-17 loss at Tampa Bay, the Colts returned home without a key defensive lineman who sustained a season-ending injury, an offensive tackle who will miss the rest of the season and questions covering everything from a brewing quarterback controversy to poor pass coverage.

I think overall we can play better,'' coach Jim Caldwell said of the defense.They got a couple of big ones (passes) against us, and then in terms of our tackling as well, we weren't as good at getting guys down as we were the week before. You've got to give some credit to a big, strong guy who was running hard in the second half, but we have to do a better job.''

The Colts, of course, want to accentuate the small positives from this dismal first month.

They say the ground game has been better, the passing game is getting in sync and the defense has steadily improved. The combination has helped Indy look more competitive against playoff contenders Pittsburgh and Tampa Bay.

But the problems are glaring, too.

Indy is one of four winless teams in the NFL. One more loss would give the Colts their first five-game skid since 2001 and their first 0-5 start since 1997, when Manning was still at Tennessee.

Painter's solid performance Monday night also will likely renew the public debate over Indy's starting quarterback, if Kerry Collins is cleared to play against Kansas City.

Caldwell didn't dare tackle the question Tuesday, less than 12 hours after the team plane landed in Indy.

We're not going to make that decision today,'' Caldwell said.I am going to tell you, he (Painter) did the things we asked him to do. He had some bright spots, but we'll see how things go in the next day or so.''

Strangely, the quarterback controversy may not even be the Colts' biggest concern this week.

The possible season-ending injury to Manning sent Indy into this tailspin, and losing defensive captain Gary Brackett and starting safety Melvin Bullitt for the season with shoulder injuries have only compounded the problem.

But the list of injured players is growing.

Eric Foster sustained a gruesome injury Monday night, a partial dislocation of the right ankle. The four-year veteran had season-ending surgery Tuesday and isn't expected to return to Indianapolis until Thursday, vice chairman Bill Polian told radio listeners Tuesday night.

Foster was one of the key cogs in the middle of the defensive line and often played alongside rookie defensive tackle Drake Nevis, who also left Monday night's game with an injury.

``Every1 is back at work on 3 hours' sleep/Players must rest all day n get treatment,if need b..I'll bring Eric back home,on my plane,midweek,'' team owner Jim Irsay wrote on Twitter.

And it may be even worse on the offensive line.

Rookie left tackle Anthony Castonzo left the Tampa game after the opening series with an ankle injury. Backup Ben Ijalana left with a left leg injury in the fourth quarter. Neither returned, meaning the Colts finished the game without their top three draft picks - Castonzo, Ijalana and Nevis.

Ijalana was diagnosed with a torn ACL, a person with knowledge of the injury told The Associated Press. The person requested anonymity because the team has not yet provided injury updates on any player other than Foster.

The injuries along the offensive line prompted Caldwell to move Jeff Linkenbach from right tackle to left tackle. He inserted Mike Tepper, who was signed off the practice squad Monday, at right tackle.

In addition, Ryan Diem, the longtime starter at right tackle who moved to right guard this season, has missed two straight games with a sprained left ankle.

``If we're going to do something, we'll probably have to do it tonight,'' Polian told listeners.

It's a mess for a winless team looking for something, anything to pull them out of this funk.

And while the Colts could shore things up by adding free agents this week, they know it won't be a cure-all.

The new guys would still have to learn the offense on a short week, and coaches would have to make sure it doesn't slow down the progression of the Colts' offense. Or leave Painter, Collins and recently signed Dan Orlovsky in more perilous predicaments than they've already faced in this brutal early season stretch.

We have to be able to get it done and we don't necessarily want to lament on the situation. It's always a challenge,'' Caldwell said.Whether you're dealing with time constraints or whether you're dealing with injuries, it's a challenge.''