LAKELAND, Fla. -- Back in 2015, Rafael Dolis was just another Triple-A reliever with big stuff and little control of the strike zone -- and then he went to Japan.

Something clicked for Dolis while playing with the Hanshin Tigers. He posted a 2.12 ERA in his debut in 2016, and emerged as the club’s closer the next season. He began issuing fewer walks, too. It took four full seasons to complete the journey, but it worked.

It’s not as simple as a change of scenery sparking a comeback, though. Dolis needed the Japanese game and, more specifically, Japanese hitters to show him what he needed to do differently.

“The hitters over there, even in the cage, it’s just foul balls,” Dolis said, laughing as he thought back to some marathon battles in Japan. “That’s why I was looking for new pitches, like the forkball. My first year, I threw two-seam fastballs for ground balls. It was foul, foul, foul. That’s why I had to learn to throw the forkball. After that? Wow. I’m feeling better now. I think I can pitch in the big leagues again.”

That forkball -- which the Blue Jays call a splitter -- was the turning point. Dolis leaned heavily on that pitch alongside his fastball, which sits in the mid-90s mph, and developed a “controlled aggression,” as Toronto pitching coach Pete Walker calls it.

In his Grapefruit League debut on Friday against the Tigers -- Detroit, not Hanshin -- Dolis worked a scoreless fourth inning, allowing only a single to Willi Castro.

“I think the [pitch] combination is extremely effective. He’s not going to be a comfortable at-bat,” Walker said. “I know he hasn’t been here pitching in a few years, but I think he’s learned a lot in Japan. I can just tell by his demeanor and mound presence.”

The next steps for Dolis, Walker added, could be to reintegrate a breaking ball to his fastball-splitter mix. Dolis has a slider, but it was pushed to the side in Japan because his two primary pitches were so effective.

Dolis’ pitch usage is a tangible way to measure the impact of his time in Japan, but the experience also changed how the 32-year-old right-hander thinks his way through an inning. That fine line between throwing and pitching can make or break careers, as Dolis well knows. The Japanese game offered him a new catalog of pitchers and influences to borrow from.

“I feel like Japanese pitchers have different mechanics. Some pitchers throw 88 or 90 [mph], and it looks like 100,” Dolis said. “I played four years over there, and I started throwing a little bit like Japanese guys. I learned a lot.”

Toronto’s bullpen opportunities are wide open and just waiting for an arm like Dolis’ to break through. Ken Giles is locked in as the Blue Jays’ closer, but the seventh- and eighth-inning roles are still being mulled over by manager Charlie Montoyo. The role once occupied by Ryan Tepera, who pitched big innings on the back end for the Blue Jays for parts of five seasons before signing with the Cubs this offseason, could make sense for Dolis if he impresses this spring.

Montoyo watched one of Dolis’ first live batting-practice sessions earlier this week, and was asked what he’d thought about it soon after. The manager answered with a wide grin and a big nod. Then, realizing that some context might help, Montoyo continued.

“If he throws like that, I could see him at the end,” Montoyo said. “Of course, Giles and then Anthony Bass and him in that mix there. He was a closer where he was, so he already knows how to deal with the pressure at the end.”