INDIANAPOLIS (AP) - Jim Caldwell's job is to make the tough calls.

Did rookie David Caldwell make a big enough impression in the preseason to earn one of Indy's 53 roster spots? How about running back Darren Evans, the hometown kid, or Taj Smith, this preseason's workhorse receiver?

By Saturday afternoon, the Colts coach must come up with answers to those questions.

In some cases, it's very, very difficult. It's a very, very thin margin of difference between a couple of guys,'' Caldwell said on a conference call Friday.Typically, we kind of leave it up to them, how we rate them and how we feel about them. They have opportunities to do so, but it's tough.''

This year, the challenge seems far greater.

Normally, coaches cut 17 players this weekend and can bring eight of those guys back starting Sunday. This year, teams are trimming rosters from 80 to 53 with no expansion of the eight-player practice squads.

Because the NFL lockout eliminated offseason mini-camps and rookie camps, coaches also have had to condense evaluations to five weeks.

None of this makes the decisions easy, especially when it could be the end of the line for a player's career.

Not surprisingly, Indy's brain trust will have some tough decisions.

Caldwell, the safety from William & Mary who is not related to the Colts coach, impressed the staff with his speed and physical play. He had a team-high 24 tackles in four preseason games and was especially aggressive in Thursday night's 17-13 victory at Cincinnati.

Evans, Indiana's Mr. Football in 2006, averaged 3.8 yards on 25 carries. He's shown good burst and vision, as exemplified on his longest run Thursday. He also showed he has the power to get in the end zone, which he demonstrated on a TD run to tie the score against Cincinnati.

And then there's Smith.

The former Syracuse receiver has been with the Colts for two seasons, primarily on the practice squad, but had a breakout preseason. He caught 12 passes for 210 yards, more than double any other receiver on the team, and two touchdowns including Thursday night's winning score after getting hurt earlier in the game.

Taj, I think, has been performing well the entire camp, but he's at a spot where it's pretty difficult in terms of the number of quality guys we have,'' the coach said.Evans has been another one, he's certainly carried the ball well and when he's had opportunities he's made some things happen. He's a tough guy. David Caldwell, he's been good and solid, and he's really tackled well and he's been all over the place. He's a guy who has made very minimal mistakes.''

That bodes well for their chances, but the numbers crunch means nothing will be certain until the cutdowns are made.

Five-time Pro Bowl receiver Reggie Wayne and starters Austin Collie and Pierre Garcon are in no danger of being let go. Former first-round draft pick Anthony Gonzalez has played sparingly because of another injury. It's also unclear whether the Colts will activate last year's big surprise, receiver Blair White, who has been on the physically unable to perform list with a back injury.

And the Colts may use a receiver spot to carry a punt-kickoff returner, too.

Indy also seems pretty stocked at running back with the recently re-signed Joseph Addai, former first-round Donald Brown and rookie draft pick Delone Carter. Evans is competing with Javarris James and Chad Spann, another Indy native, for what is likely to be the other running back job.

Injuries are complicating things, too.

With the uncertainty surrounding Peyton Manning's playing status for the Sept. 11 opener at Houston, the Colts are likely to keep three quarterbacks instead of two.

Keeping White inactive, would mean he'd have to sit out the first six games.

But those decisions could take eliminate two jobs, spots that might normally go to undrafted rookies such as David Caldwell and Evans or a veteran like Smith.

That's what we'll kind of work our way through here,'' Jim Caldwell said when asked about the numbers game.We have some idea, but nothing is etched in stone yet.

With the amount of time that we have, we're doing the best job we can,'' he added.We think we have, from the information we have gathered, we think we can make the right decisions.''