Tony Stewart is a man at peace as he heads into the final season of his NASCAR career.

He's satisfied with what he's accomplished and has no regrets about the three glaring holes on his resume. Stewart is also adamant that his struggles the last two years, on and off the track, have nothing to do with his decision to retire at the end of this season.

The three-time NASCAR champion reiterated Thursday he'll race in other series after this year — but not the Indianapolis 500 — and his decision to leave the Sprint Cup Series is simply about giving himself more free time to pursue everything that's been on hold the last three decades.