P.J. Williams intercepted Tom Brady and returned it 40 yards for a touchdown with 1:24 left, helping New Orleans seal a dramatic but potentially costly 36-27 victory over the Tampa Bay Buccaneers on Sunday during which Saints quarterback Jameis Winston injured his left knee.

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Winston was injured during a scramble early in the second quarter when he was pulled down from behind by former LSU star Devin White, who was flagged for a horse collar tackle.

"I think it’s significant," coach Sean Payton said. "He felt something and is on crutches right now. ... When he got up and then had to go back down, you were a little concerned."

Backup Trevor Siemian took over for Winston and completed 16 of 29 throws for 159 yards and a touchdown without a turnover, leading the Saints on five scoring drives that produced two touchdowns and three field goals.

Brady passed for four TDs, but also turned the ball over three times on a pair of interceptions and a fumble, which the Saints converted into 16 points.

The Bucs nearly overcame their mistakes, wiping out a 16-point second-half deficit, taking a lead with 5:44 to go when receiver and former LSU track athlete Cyril Grayson was left uncovered behind the defense and scored a 50-yard touchdown.

New Orleans responded by driving for a field goal for a 29-27 lead with 1:41 left, leaving Brady, who is no stranger to late comebacks, that much time plus a timeout to win the game. Instead, the Saints' defense came up big.

New Orleans' defense came up with two turnovers in the second quarter after Winston was carted to the locker room, and the Saints' offense converted those into nine points.

Brady fumbled on a double-pump caused by pressure from defensive end Cameron Jordan, and defensive tackle David Onyemata, newly activated after a six-game suspension, recovered near midfield.

The Saints got a field goal, but only after a roughing-the-passer call against William Gholston wiped out what would have been an interception by Antoine Winfield Jr. in the end zone.

Later, Brady was intercepted by C.J. Gardner Johnson, who had left his man to undercut a pass intended for Godwin. Gardner-Johnson returned the ball 26 yards to the Tampa Bay 35.

New Orleans converted that on a short pass from Siemian to fullback Alex Armah shortly before the end of the first half, giving the Saints a 16-7 lead after rookie kicker Brian Johnson missed the extra point.

New Orleans widened its lead to 23-7 on the opening possession of the second half, which began with Siemian hitting Kevin White for a 38-yard gain. Alvin Kamara finished it with a scoring run on a pitch play on fourth-and-goal from the 1.

But Brady responded by leading the Bucs to the end zone on their next two possessions on a 7-yard pass to running back Giovani Bernard and a 41-yard strike to Mike Evans. He beat Saints top cornerback Marshon Lattimore in single coverage and made it a 23-21 game before the third quarter ended.

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INJURIES

Buccaneers: Tight end Rob Gronkowski, who'd missed the Bucs' previous four games with ailing ribs, played only briefly before being ruled out with back spasms.

Saints: In addition to Winston's injury, reserve defensive tackle Montravius Adams and defensive end Carl Granderson received attention in the injury tent.

UP NEXT

Buccaneers: enter their bye week before visiting Washington on Nov. 14.

Saints: Host Atlanta next Sunday.