CBS Sports points out the obvious--the Colts are bad on third down:
The Colts are having a tough time converting on third downs from an offensive standpoint. And Indianapolis isn't doing a very good job of getting opposing offenses off the field on third down. Through two games, the Colts are just five of 23 (28 percent) in third-down conversions. And they've allowed teams to be 13 of 27 (48 percent) in third-down conversions.