Whisenhunt, 51, will be introduced at a news conference Tuesday.
Whisenhunt spent six years coaching Arizona and took the Cardinals to their lone Super Bowl in 2009. He was fired Dec. 31, 2012, with a record of 45-51 in the regular season and 4-2 in the playoffs.
He interviewed with Cleveland twice last year before being hired as offensive coordinator in San Diego, where he helped Philip Rivers and the Chargers to the playoffs.
Whisenhunt, who started his coaching career in Nashville at Vanderbilt, will replace Mike Munchak, who was fired on Jan. 4.
The Tennessean reported the Titans interviewed Cincinnati defensive coordinator Mike Zimmer for a second time Monday in Houston before hiring Whisenhunt.
Brees open to pay cut
After leading the Saints to a fourth playoff appearance in five seasons, Drew Brees likes the direction of his team and says he's willing to listen to contract proposals if the team needs his help getting under the NFL's salary cap.
Brees says he'll consider whatever "puts the best team on the field," and would be interested in extending his five-year, $100 million deal beyond the three years it has left.
With coach Sean Payton returning from his bounty suspension, the Saints returned to the playoffs before falling at Seattle 23-15 on Saturday.
Brees eclipsed 5,000 yards passing and New Orleans' defense improved dramatically under first-year coordinator Rob Ryan.
Now the Saints have to find salary cap space to keep top free agents such as tight end Jimmy Graham.
P New England at Denver, 1 p.m., Ch. 2
• San Francisco at Seattle, 4:30 p.m., Ch. 13