The Titans, the second NFL team to fire a coach this season, are 1-6 this season and went 3-20 during Whisenhunt's tenure.
In addition to the losing, management was concerned about the Titans' inability to protect rookie quarterback Marcus Mariota. They have allowed 28 sacks, and club President Steve Underwood said controlling owner Amy Adams Strunk wants the team to do everything possible to preserve Mariota, including keeping him out of games if necessary to heal. The franchise hasn't been to the playoffs since 2008, and Mariota is the third quarterback it has drafted within the first eight picks in the last decade.
Mularkey is a former head coach with Buffalo and Jacksonville and was a finalist in Tennessee in 2011 before Mike Munchak was hired. Strunk, who was not at Tuesday's news conference, took over as controlling owner in March, replacing Tommy Smith, who gave Whisenhunt a five-year contract in January 2014.
Allen's season is over
San Diego put wide receiver Keenan Allen on season-ending injured reserve because of the kidney injury he suffered Sunday while making a spectacular touchdown catch in a loss to Baltimore. Allen is second in the NFL with 67 catches and third with 725 yards receiving.
Colts fire offensive coordinator
Indianapolis fired offensive coordinator Pep Hamilton and installed associate head coach Rob Chudzinski, a former head coach in Cleveland, as the play-caller. Coach Chuck Pagano, who has faced criticism with the Colts floundering at 3-5, said the offense hadn't played with the necessary consistency.
49ers sign Thomas
San Francisco signed running back Pierre Thomas to bolster a position hit by injuries, adding to a wild two days of change that included the benching of struggling quarterback Colin Kaepernick and the trade of tight end Vernon Davis. The team placed running back Reggie Bush (knee) on season-ending injured reserve, and the NFL suspended defensive lineman Kaleb Ramsey for four games for violations of its policy on performance-enhancing drugs.
Protest in Carolina
The NFL and the Carolina Panthers still don't know how protesters got rappelling gear into the team's stadium and suspended themselves by cables from the upper deck during Monday's night's game against Indianapolis. The team said the protesters got into the game with tickets purchased through NFL Ticket Exchange. Police arrested four people — the two who rappelled and two who assisted them — and charged them with second-degree trespassing and resisting a public officer. The people arrested held up banners protesting against Bank of America, which owns the stadium's naming rights.
Dallas waived embattled running back Joseph Randle, its No. 2 rusher with 315 yards. Randle was already away from the team to deal with an unspecified personal issue and had been ruled out of Sunday's loss to Seattle with a back injury before he took the personal time.
Pittsburgh said veteran DeAngelo Williams will start at running back in place of All-Pro Le'Veon Bell, who is out for the season after suffering a knee injury.