Gay kicked a 40-yard field goal with 2:36 remaining in the game to put the Rams ahead 27-24, and Rams safety Jordan Fuller intercepted quarterback Tom Brady with 1:57 remaining to secure the win and improve to 7-3.
"You can't write it," Gay said. "It's one of those stories that you're sitting on the practice squad, and then the first game you're activated, you're going back to the place you were last year and the place you felt like you should have been and play on prime time on Monday Night Football. There was a lot of emotion for me coming back in."
The Buccaneers selected Gay with a fifth-round pick in 2019 but waived him before this season. The Rams signed Gay last Monday from the Indianapolis Colts' practice squad. He arrived in L.A. later that day and entered COVID-19 protocol before he was able to join the team on the practice field Saturday, two days before facing the Bucs.
Gay converted two of three field goal attempts Monday. He made a 38-yard kick in the first quarter to give the Rams a 17-14 lead, then missed a 44-yard attempt with the game tied at 17 in the third quarter before he converted a 40-yard kick that put the Rams up for good.
"Watching the way Matt handled himself throughout the game, you could feel there was a lot of confidence," Rams coach Sean McVay said. "I know he had the one miss, but you can tell the difference between a 'miss' and then one of those where 'that looks a little shaky.' He was true all night. Great height, good timing, and he was very accurate. I loved what he did. It was a great snap, great hold, great operation. He made it, and it was as true as it gets."
As a rookie in Tampa Bay last season, Gay converted 27 of 35 (77.1%) field goal attempts and made 43 of 48 (89.6%) extra points. He lost the job in training camp this season to veteran Ryan Succop.
Gay said Monday that L.A. punter Johnny Hekker was instrumental in the Rams' decision to sign him.
"Johnny texted me and said he really wanted me here," Gay said. "He said he personally texted Sean McVay to go to bat for me."
Samuel Sloman, a seventh-round pick from Miami (Ohio), won the starting job over Lirim Hajrullahu and Austin MacGinnis out of training camp but was unable to consistently convert field goals and struggled on kickoffs.
The Rams cut Sloman after Week 7 and signed veteran Kai Forbath, who also proved to be inconsistent before he suffered an ankle injury in Week 11 and was placed on injured reserve.