What's slowing the Indianapolis Colts?

You talk about a team destroyed by injuries. The Colts did not play T Tony Ugoh, G Mike Pollack, SS Bob Sanders, TE Jacob Tamme, WR Roy Hall, DT Daniel Muir, DE Curtis Johnson, and DE Marcus Howard in Week 3.

TE Dallas Clark played and was hurt again. Center Jeff Saturday was active after missing the first two weeks.
The result is an offense that is ranked 24th in scoring and a defense that is ranked 20th in points allowed. The result is a 1-2 team that currently sits in third place in the division.

The last time the Colts started a season 1-2 was 1998 when the Colts started 1-8. Peyton Manning was only a rookie then.
You cannot have three offensive linemen and a starting tight end hurt and expect to run the ball. Joseph Addai has 43 rushes for 142 yards, 3.3 yards per carry, and three touchdowns. He can't go out in pass routes as much so he has only four catches for 26 yards. As a result the Colts are completely one-dimensional.

They rank second in pass attempts as opposed to 30th in rush attempts. Peyton Manning is on pace for 4,181 yards this season, but with only 16 touchdown passes and 21 picks. He is completing 59.1 percent of his passes and has a rating of 73.1. This for a guy that has never had less than 26 touchdowns in his career, has a career QB rating of 94.2, hasn't had more than 15 interceptions since 2002, and has a career 64.1 completion percentage.

Peyton Manning has plenty of time to turn his season around. What this does show is what I tell people time and time again. Quarterbacks can carry teams in stretches. They can occasionally will a team to victory. But they can't be the team.
Even someone as gifted as Peyton Manning needs his offensive line to block. He needs Addai to give the offense rushing balance. He needs more than Reggie Wayne, Marvin Harrison, and Anthony Gonzalez to catch the ball downfield. Receivers aren’t very effective without running games that keep safeties and linebackers honest.  

Dallas Clark is a big part of this offense. While Manning is still getting yards, they aren't coming as efficiently as they normally do.
The other concern has to be Bob Sanders. The Colts weren't good at stopping the run with him in their first two games. In his first game out, both Maurice Jones-Drew and Fred Taylor (who had been ineffective in their first two games) rushed for over 100 yards. If teams can run the ball effectively, it will keep Manning on the bench and limit his opportunities even more.

Indianapolis has to go back to the drawing board quickly. With the second toughest schedule in the NFL this season (based on ‘07 record) they can't afford to keep losing games. They are already two games back in the division and have lost two games at home. 

Their bye week couldn’t come at a better time.