Josh Allen’s 7-yard touchdown pass to Duke Williams in the fourth quarter lifted the Buffalo Bills to a 14-7 victory against the Tennessee Titans in a defensive battle Sunday in Nashville, Tenn.Allen, who took a hit to the head from New England’s Jonathan Jones last week, had been in concussion protocol until Saturday morning. He finished 23 of 32 for 219 yards, two TDs and one interception for the Bills (4-1).Allen found Williams in the end zone to give Buffalo a 14-7 advantage with 9:46 left in the fourth. The six-play, 77-yard drive was highlighted by Isaiah McKenzie’s 46-yard reception.Williams, who previously played in the Canadian Football League, was activated from the Bills practice squad on Saturday.Tennessee’s Cairo Santos missed all four field-goal attempts, including a 33-yard try that would have provided a lead with 12:27 left in the fourth. He also missed a 53-yard try with 6:31 on the clock.Marcus Mariota finished 13 of 22 for 183 yards for the Titans (2-3).Tennessee’s Derrick Henry had a 1-yard TD dive to tie the score at 7-7 with 7:02 remaining in the third quarter. The score was set up by Kevin Byard’s interception that started the drive on Buffalo’s 38-yard line.The Bills held a 7-0 halftime lead thanks to Allen’s 8-yard scoring pass to tight end Lee Smith with 2:36 left in the second quarter. Allen was 5 of 5 on the six-play, 60-yard touchdown drive that consumed 2:46.