He played college football for the Oklahoma State University Cowboys, and was selected by the Indianapolis Colts in the sixth round of the 2006 NFL draft.

Johnson's performance during 2007 was widely viewed by fans as a disappointment (that season marked the first time in five years that the Colts finished out of the top 5 in least sacks allowed), considering the competence he had shown as a rookie.

In Johnson's third season, he was moved to left guard in order to compensate for the loss of injured starter Ryan Lilja.

The following year, Johnson beat out underachieving starter Tony Ugoh for the starting LT position during training camp.

On December 18, 2012, Johnson appeared on an episode of Ink Master, where he received a tattoo of a dragon on his right forearm by contestant Tatu Baby.