He has agreed a four-year contract, reportedly worth $2.5m [�1.27m] a year, as only the Steelers' third coach in 38 years, and their first-ever black one.

Tomlin was hired on the same day black coaches - Chicago's Lovie Smith and Tony Dungy of Indianapolis - made the Super Bowl for the first time.

He replaces Bill Cowher, who guided the Steelers to Super Bowl victory in 2006.

Cowher coached Pittsburgh for 13 seasons and was contracted through the 2007 campaign, but announced he was quitting earlier this month.

Th Steelers were just 8-8 this season and missed out on the play-offs.

Tomlin's hiring completes a search in which he was initially viewed as an unlikely choice behind perceived front-runners Ken Whisenhunt and Russ Grimm.

Whisenhunt later took over as head coach with the Arizona Cardinals.

Bears defensive co-ordinator Ron Rivera did not get a second interview, ironically because of Chicago's success in reaching the Super Bowl.

The Steelers would have had to wait until after the big game on 4 February to meet with him again.

Georgia Tech coach Chan Gailey, recommended by Cowher, also failed to get a second interview.

The 34-year-old Tomlin will be the fourth consecutive Steelers coach who was a defensive assistant coach in his 30s with another team before being hired.

Bill Austin was 37 when he was chosen in 1966, as was Chuck Noll in 1969. Cowher was 34 in 1992.

What could be tricky is assimilating Tomlin's preference for the 4-3 defence into a Steelers system that has been built around the 3-4 since 1983.