This story was excerpted from Ian Browne’s Red Sox Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

FORT MYERS, Fla. -- Justin Slaten was stuck in the Texas Rangers’ farm system. A third-round selection in the 2019 MLB Draft out of the University of New Mexico, the hard-throwing righty finally got to Triple-A Round Rock for the final five games of last season.

But Slaten’s strong showing in that cameo (1.08 ERA and 10 strikeouts in 8 1/3 innings) wasn’t enough to convince the Rangers to protect him heading into last December’s Rule 5 Draft. The Mets scooped him up for just a minute, but only so they could deal him to the Red Sox for Minor League lefty Ryan Ammons and cash considerations.

Boston’s newly constructed pitching department under chief baseball officer Craig Breslow targeted Slaten heading into the Rule 5 Draft as someone who had the potential to be a late bloomer at 26 years old.

The reliever is now unstuck in Boston, all but certain to make the Opening Day roster.

Rule 5 picks can make a roster decision tough on clubs for obvious reasons. That player must be on the 26-man roster for the entire season or be put on waivers. If nobody claims the player, he must be offered back to the team that left him unprotected.

Rest assured that Slaten is not making life tough on the Red Sox with his lights-out Spring Training. Quite the opposite, actually.

“He’s actually making it easy,” said Red Sox manager Alex Cora. “He’s been throwing the ball excellent. Everything we’ve thrown at him, he adds to the games. The stuff is really good. Holding runners, he’s been quicker. The placement of his hands, all that stuff. All the little things that make you a good big leaguer, he’s been great about.”

Three years ago, the Red Sox went down this Rule 5 road with Garrett Whitlock. For a team that went to the American League Championship Series in 2021, Whitlock emerged as an invaluable bullpen piece.

Slaten is hoping history repeats itself. In fact, Whitlock was the one who calmed him before his first Grapefruit League outing against the Orioles on Feb. 24.

“He was honestly the one who kind of came up to me before the first Spring Training game in Sarasota,” Slaten said. “And he was like, ‘Hey man, you’re not going to make the team today and you’re not going to not make the team today. Just go out there and have fun and enjoy and try and take it day by day.’ That was the advice that he gave me.”

To Slaten, Whitlock -- who is close to locking down a spot in the starting rotation -- is living, breathing proof of a Rule 5 Draft pick who made good.

“It feels good to see that there's another person in this clubhouse who was in the same boat as me and who has had success,” Slaten said. “Looking at what he's done, it definitely makes me feel good about this situation I’m in.”

In five Grapefruit League outings, Slaten has allowed one unearned run on just two hits, walking one and striking out six over 5 1/3 innings. His fastball has been in the upper 90s.

“For him and for all these guys that are Rule 5, they don’t want to go back,” said Cora. “They want to stay here. They want to be big leaguers. Most of the time when you go back to the other organization, you’re not going to be in the big leagues. This is his shot right now, and he’s throwing strikes and we’re very happy with the way he’s been going.”

For Slaten, the waiting game he went through in Texas is finally paying off. He could be the classic case of a guy who took a while to get his whole arsenal clicking and just needed a fresh set of eyes to help him get to the next level.

“I mean, it's hard when you get drafted out of college and look back at some of the guys that were in your Draft class [and] they are two to three years into their career,” said Slaten. “It is hard because you want to get up there as soon as possible.

“I definitely had some lumps in my career. There were a lot of learning curves. Mechanically, I went through changes, learning how to throw new pitches to help me. At times you wonder why it takes so long, but at the end of the day, everybody gets where they're supposed to be going whenever they're supposed to be there. So it's just the mentality that I have about it. And that’s just kind of how I view it.”