MANKATO -- The moves just keep on coming.

The Vikings signed free agent offensive tackle Charlie Johnson this morning. Johnson, who played college football at Oklahoma State, was a sixth-round pick by Indianapolis in 2006.

The 27-year-old has played in 73 career games, starting 54 of those. Johnson, 6-4, 305 pounds, appeared in 10 playoff games with the Colts.

He had played left tackle for the Colts -- yes, that is Bryant McKinnie's position -- but reportedly could have been moved to guard had he stayed in Indianapolis.

Johnson started 15 games at left tackle last season and 12 in 2009. In 2008, he started 12 games at left guard and four at left tackle. It will be interesting to see where the Vikings have him working on an offensive line that has some question marks. (Among them is that right guard Anthony Herrera is expected to open camp on the physically unable to perform list.)

The Vikings roster is now at 90 players, the maximum for the opening of training camp.