JUPITER, Fla. -- Three years ago, Marlins right-hander Anthony Bender entered big league camp as an unknown. Now, he could be the X-factor.

Bender, who underwent Tommy John surgery on Aug. 30, 2022, returned to the mound for the first time since the procedure and tossed a scoreless third inning in the Marlins' 6-3 loss to the Nationals on Sunday at Roger Dean Chevrolet Stadium.

“Exciting for sure,” Bender said. “Last night seeing my name on the lineup, going out there, getting ready for today, felt really good getting back out there for the first one.”

The 29-year-old Bender showed rust and potential in his outing. That’s to be expected considering the length of time he was away from game action. His first pitch was a 95.6 mph sinker. Three offerings later, he struck out Trey Lipscomb with his trademark slider.

After two quick outs, Bender permitted a two-strike single up the middle, followed by a steal and an eight-pitch walk to warrant a mound visit from pitching coach Mel Stottlemyre Jr. Bender didn’t need another pitch, however, as he picked off the lead runner at second for the final out.

Overall, Bender threw 19 pitches (12 strikes) and maxed out at 96.9 mph, below his average velocity in 2022 (97.7 mph, 96th percentile). He threw 15 sinkers and four sliders, turning to the latter as a putaway pitch. Later this spring, he might break out a changeup.

“You can't have any pitches better than what he has,” catcher Christian Bethancourt said. “He showed it today. I think he was just missing a little bit arm side, and I think that's just natural for a guy that throws that angle. Pitches were moving, pitches were really hard, and that's what you want to see from him.”

Miami signed Bender to a Minor League deal on Nov. 30, 2020, after discovering him at a Milwaukee Milkmen game in the Independent League. Bender had previously spent four seasons in affiliated ball but never advanced past Double-A.

But Bender quickly emerged at 2021 Spring Training, tossing 8 1/3 scoreless innings to make the Opening Day roster as a non-roster invitee. That domination continued into the regular season, as he didn’t permit an earned run through his first 21 outings. According to Baseball Savant, Bender's sinker had 6.3 inches above average of vertical movement -- eighth best among Major Leaguers with at least 250 pitches. His slider had four inches above average of vertical movement, which ranked 20th of big leaguers.

By 2022, Bender opened as the club’s closer. Things turned when the training staff noticed Bender flexing his arm and flicking his wrist following a ninth-inning strikeout on Aug. 13, 2022. He underwent Tommy John surgery 17 days later.

Much has changed since the last time Bender took the mound in a game. There is a pitch clock. There are new faces in the front office and on the coaching staff. The rebuilding club aiming to turn the corner into contention is instead hoping to reach the postseason for a second straight fall.

While all that happened, Bender rehabbed in Jupiter along with Miami’s No. 3 prospect Max Meyer. Bender would return home to watch games from his couch as the days blended together and his body healed. As Bender progressed, there was consideration for his return in the National League Wild Card Series.

“It was close,” Bender said. “It would have been right at the playoff time, going from not pitching in front of anyone to however many Philly holds. Probably wouldn't have been the smartest thing. I know I definitely wanted to, and I was itching to get back there, but I just missed it, which is unfortunate.”

During the Marlins’ postseason chase, they relied heavily on a quartet of southpaw relievers: Tanner Scott, Andrew Nardi, A.J. Puk and Steven Okert. The front office acquired veteran David Robertson to add a righty to the mix.

With Puk a rotation candidate and Okert in Minnesota, Bender has the chance to again be a reliable high-leverage arm.

“We had [Matt] Moore and Robertson last year late in the game, and someone is going to have to replace those big innings, especially if Puk is in the rotation,” manager Skip Schumaker said. “Somebody is going to have to get those innings when Tanner's not available or Nardi's not available. Someone's going to have to step up. He's had experience in the back end and been really good at it. Hopefully we see that, and it really lengthens our bullpen. But it also helps guys when they're down or helps our team when they're down.”