The turnovers could have hurt the Titans much more, but Indianapolis consistently failed to take advantage. Mathis' forced fumble led to a four-play, 1-yard drive that ended with Vinatieri's fifth field goal for the 15-14 lead with 1:14 left in the third quarter.
Vaughn's second interception on the ensuing drive set the Colts up with a first down at the Titans' 48-yard line, but they gained just six yards on three plays and punted the ball away.
All of the team's offense in the first three quarters came on Vinatieri field goals from 47, 48, 45, 37 and 49 yards out.
Tennessee twice took the lead, first with a 1-yard touchdown run by Fitzpatrick to make it 7-6 early in the second quarter and then with a 1-yard pass from Fitzpatrick to running back Chris Johnson to go up 14-12 midway through the third.
The Colts didn't panic, clawing back each time before putting the game away at the end. In the process, Indianapolis improved to 9-0 following a loss with Luck under center.
"Very seldom do you not have a speed bump or a road block (during an NFL season)," Vinatieri said. "But the good teams figure out a way to kind of get that behind you and keep moving forward. The great thing about this team, it has a ton of heart, a lot of resilience. We just find a way to go back out there and clear what happened the week before and just keep moving forward. So, hopefully, we can just keep building on this one."