The Cincinnati Bengals signed the left tackle to a one-year contract extension through 2016, NFL Media's Albert Breer reported, according to a team source.
NFL Media Insider Ian Rapoport adds the extension is worth up to $9 million, per a source who has seen the deal.
ESPN first reported the news.
Whitworth, the oldest starting tackle in the NFL, has had an outstanding start to the season, rated the No. 3 overall tackle by Pro Football Focus through two games. The Bengals' offensive line has yet to allow a sack and has road graded in the run game, helping Cincy to the No. 3 rushing offense (151.0 yards per game).
Whitworth entered 2015 with $5 million on his final year. Smith's contract is also set to expire after this season, so adding another year to Whitworth's deal ensures the Bengals will retain at least one of their veteran tackles as they bring along the young blockers.