Here's Day 3 of the five-day series looking at the five most competitive position battles
Primary candidates: Thornton, Mewhort, Thomas and Louis
Pro: Thornton was forced into the starting lineup as a rookie last season. He started 14 games after Thomas went down with a torn tendon in his quad and bicep. Thornton appears to have the inside track on keeping his starting spot because he worked with the first team during offseason workouts.
Con: Thornton got experience by starting those 14 games, but he struggled and he was definitely part of those interior problems.
Pro: He showed the coaching staff enough to go from being with the second unit during the first part of offseason workouts to working with the first unit by the end of their three-day minicamp. Mewhort's locker is also right next to quarterback Andrew Luck.
Con: Mewhort played tackle during his final season at Ohio State. Mewhort starting would mean that the interior part of the offensive line would consist of a rookie, a second-year center who is basically a rookie and a second-year guard. That's a lot of inexperience there.
Pro: Thomas has started 23 of the 45 games he's appeared in during his career. Colts GM Ryan Grigson believes Thomas has gotten stronger in his lower body.
Con: Thomas is behind the rest of the group because he didn't participate in any of the offseason workouts since he's still working his way back from his injuries last season.
Pro: Louis has started 28 of his 41 career games. He started 24 of a possible 25 games during the 2011 and 2012 seasons with the Chicago Bears.
Con: Louis didn't play in the league last season after tearing his ACL in November 2012. So he's not only learning a new system, he's also getting comfortable playing football again on that knee. Louis started out working with the first team in the offseason before being passed by Mewhort.