TAMPA, Fla. — Austin Davis played with the poise and resolve of a seasoned pro.

“We never panicked,” veteran tackle Jake Long said Sunday after Davis led a late field goal drive that gave the St. Louis Rams a 19-17 victory over the Tampa Bay Buccaneers on Sunday in the 25-year-old quarterback’s first NFL start.

“It’s special. I can’t really describe what I felt,” Davis, a third-stringer when training camp began, said after receiving a game ball from coach Jeff Fisher. “I felt a peace out there. I felt at home, and it had a lot to do with the guys I was around and how well we played.”

Greg Zuerlein’s fourth field goal of the day, a 38-yarder with 38 seconds remaining, won it.

Davis threw 13 yards to Lance Kendricks on third-and-1, 15 yards to Brian Quick on second-and-9, and 27 yards to Austin Pettis on third-and-9 to set up the winner.

“I can’t say enough about Austin. … I felt like he’d be OK because of the entire weeks’ worth of preparation,” Fisher said. “He was very poised. … Nothing overwhelming to him. He made really good decisions against a good defense, an injury-depleted defense, but a good defense.”

Davis completed 22 of 29 passes for 235 yards with no interceptions. Zac Stacy had a 2-yard touchdown run in the first quarter, and Zuerlein also made field goals of 36, 35 and 46 yards to help the Rams (1-1) rebound from a lopsided season-opening loss to Minnesota.

Davis made his debut in that game after Shaun Hill was injured, throwing for 192 yards but also having an interception returned for a touchdown.

“He made good decisions and handled the run checks very well. He did well with the play action stuff,” Fisher said. “He gave receivers opportunities to make plays. … Credit the offensive line, too. We ran the football and we protected fairly very well.”

Bobby Rainey rushed for 144 yards and quarterback Josh McCown had two short touchdown runs for the Bucs (0-2), who moved the ball into St. Louis territory in the closing seconds only to have the game end when rookie Mike Evans was slow getting up after a 29-yard reception to the St. Louis 32.

Officials stopped the clock with 8 seconds remaining and Evans was eventually helped off the field, But by rule, an injury in that situation requires a 10-second runoff, and the remaining time was wiped off the clock.

“Unfortunately he just took a hard hit. Mike was just trying to find his bearings, I think, and so the refs blew (the whistle for an injury timeout), I guess. It’s unfortunate because I felt like we were getting to the spot where we wanted to let (kicker Patrick Murray) take a swing at it.”

McCown scored on runs of 1 and 5 yards. Rainey, filling in for the injured Doug Martin, helped the Bucs move into position for Murray to kick a 36-yard field goal to give Tampa Bay a 17-16 lead with 5:15 remaining.

But a defense playing without tackle Gerald McCoy and middle linebacker Mason Foster couldn’t keep Davis from leading the Rams on a 12-play, 71-yard drive to win the game.

With Sam Bradford out for the year with a knee injury and Hill hobbled by a thigh injury, Davis prepared the entire week to be the starter.

Hill was active Sunday, however Fisher didn’t waver on his decision to go with Davis, who spent most of the past two seasons on the Rams’ practice squad.

“At no point was there a chance for Shaun to start. … It couldn’t have worked out better for him,” Fisher said. “Again, he’ll be day to day next week. This week really helped him, and another week will significantly help him put this thing behind him.”

McCown, a career backup entering a season as a starter for the first time in a decade, completed passes of 18 and 20 yards to Vincent Jackson before Rainey broke a 10-yard run to set up the quarterback’s second TD made it 14-10.

The Bucs threatened again on their next possession, driving deep into Rams territory before Murray’s 26-yard field goal attempt was blocked by T.J. McDonald.

The Bucs also had a punt blocked, leading to a Rams field goal. McCown also threw a first-quarter interception that stopped a drive inside the Rams 10.

“That was a tough one to lose. Anytime you have a blocked punt, blocked field goal, in the red zone getting ready to put points on the board and you throw an interception, you’re not going to win many games,” Bucs coach Lovie Smith said. “We got ourselves back in position at the end, and it’s unfortunate we didn’t handle the situation as well as we needed to there at the end.”

Notes: Play was stopped for 51 minutes in the first half because of severe weather. … Hall of Famer Derrick Brooks was inducted into the Buccaneers Ring of Honor. The 2002 NFL defensive player of the year also had his No. 55 jersey retired and received his Hall of Fame ring during the halftime ceremony. … Stacy rushed for 71 yards on 19 carries and Brian Quick had seven receptions for 74 yards for St. Louis. … McCoy left with a broken left hand and Foster left with a shoulder injury. … The Rams played part of the game without receiver Tavon Austin, who clutched his right knee after being tackled by Mark Barron.