Mike Vrabel declared "we're not dead yet" after the Tennessee Titans fought back to beat the San Francisco 49ers 20-17 on Thursday.

The Titans were 10-0 down at half-time, but touchdowns from D'Onta Freeman and the returning A.J. Brown put them in front.

Niners quarterback Jimmy Garoppolo, who completed 26 of 35 passes for 322 yards, threw his only TD pass for Brandon Aiyuk to level the game in the fourth quarter.

Randy Bullock had the final say, though, making no mistake with a field goal with four seconds left, ensuring Tennessee (10-5) can win the AFC South if the Arizona Cardinals beat the Indianapolis Colts on Sunday.

Titans head coach Vrabel said: "The funeral for the Titans was supposed to be yesterday or today. We're not dead yet."

Brown was making his first appearance since Week 11 after recovering from a chest injury and certainly made his presence felt.

The wide receiver took a career-high 11 catches for 145 yards and was able to celebrate a long-awaited touchdown.

Vrabel said of Brown: "We understand how important he is to our football team. Love him as a person. Glad to have him back."

He added: "A.J''s fantastic. We expect those things from A.J."

Ryan Tannehill threw 22 of 29 passes for 209 yards while Brown finished with 11 receptions for 145 yards.

Defeat for the 49ers (8-7) ensured the Dallas Cowboys (10-4) will feature in the playoffs for the first time in three years.

Dallas (10-4) clinched its first playoff berth in three years Thursday, thanks to the Tennessee Titans' 20-17 victory over the San Francisco 49ers.