TAMPA, Fla. -- The Red Sox had their first and only off-day of Spring Training on Monday, and it would have been a great day for a 22-year-old third baseman to sleep in.

That's what Rafael Devers surely would have done last year or the year before. But it is a newly committed Devers entering his third season in the Major Leagues, and never was that commitment more clear than Monday.

"[Devers] and Xander [Bogaerts], they showed up at 8 o'clock in the morning to go to the gym, and they were running sprints," said Red Sox manager Alex Cora. "People saw them and everybody was surprised. It was actually Xander trying to catch up with Devers, as far as the workouts and all that. He’s in a great place, man. I'm very proud of Raffy."

Devers, who went 1-for-3 in Friday's 14-1 loss to the Yankees, has a different look about him this spring. And it has nothing to do with his .438 batting average in Grapefruit League competition.

The physical part is obvious. He is noticeably trimmer, and it is paying off. That could be seen in the bottom of the first inning against the Yankees, when Devers got a tricky hopper over the bag and made a strong throw across the diamond from an off-balanced position to nail Luke Voit at first. Cora had referenced a similarly athletic play that Devers made on Thursday against the Tigers.

"I worked a lot on my defense in the offseason and made it a point to work a little extra on it and just trying to look as best as I can out there on the field and just in general," Devers said.

The mental part is also easy enough to spot. Devers has a constant joy and energy about him as he goes though the monotony of Spring Training.

"I just feel 100 percent right now," Devers said.

The momentum started in the winter.

"He made a commitment," Cora said. "He got a strength-and-conditioning coach in the Dominican, a nutritionist in the Dominican. He's doing the same thing here in Fort Myers, so he understands. You see the guys around him, how they go about their business, J.D. [Martinez], Mookie [Betts], Jackie [Bradley Jr.], and you learn from them. He's only 22. Sometimes we take him for granted. He's still a kid, and he's still learning.”

One thing Devers learned last year was that you can't get into shape during Spring Training. That approach led to Devers serving three stints on the injured list due to nagging injuries.

"We challenged him," Cora said. "I think [trainer] Brad [Pearson] brought up a good point at the end of the season that he always, when the season started, he was always in shape. Sometimes it took him longer. And it was in Spring Training.

"Instead of just going through his progressions, it was that and you'd have to do a little bit more. And then during the season, it gets to the season where you get tired because of what he did in Spring Training. It's not like it was fat camp or stuff like that. He was a few pounds overweight, just a little bit. More sprints, more cardio, and then toward the end of the season, he felt it. This year, it's been the other way around. It's just a regular camp working on his swing and working on his defense. He made a commitment."

If Devers continues to impress, he could spend his share of time hitting third in Boston's loaded lineup. That would be after Betts and in front of Martinez. Forgive Devers if his eyes light up at the thought.

"It's a big job, but it's one that I'm ready for if given the opportunity," Devers said. "I'm just ready for whatever position they put me in the lineup. The best feeling for me is just to be in the lineup, period."

Devers hasn't hit his ceiling yet, but his manager has a pretty good idea of what it could look like.

"I think he has the potential -- and everybody knows it here -- to have a monster year offensively,” Cora said.