PITTSBURGH -- One of the NFL's longest-tenured head coaches is extending his stay in Pittsburgh.

The Steelers announced an extension for Mike Tomlin, who is now under contract through at least the 2021 season.

Tomlin had two years left on his deal, and the team added an additional year plus an option year, a source told ESPN. His contract is aligned with that of quarterback Ben Roethlisberger, whose deal goes through 2021.

"Mike is one of the most successful head coaches in the National Football League, and we are confident in his leadership to continue to lead our team as we pursue our goal of winning another championship," team president Art Rooney II said in a statement.

Since his 2007 hiring, Tomlin has not had a losing season and has won at least 10 games in eight of his 12 years. Among active head coaches, only New England's Bill Belichick and New Orleans' Sean Payton have logged more years in their current jobs.

"I am very appreciative of this contract extension and opportunity and want to thank Art Rooney II and everyone in the organization for the support in my first 12 seasons," Tomlin said in a statement. "We have a goal of winning the organization's seventh Super Bowl championship, and I couldn't be more excited about this upcoming season."

The Steelers have typically extended Tomlin's contract every other year around training camp. In 2017, the team agreed to a two-year extension with the coach.