GOODYEAR, Ariz. -- Indians right-hander James Karinchak threw 30 1/3 innings across three Minor League levels last season and struck out 74 batters -- that’s 81.3 percent of his outs coming by strikeout.

If those numbers are piercing, imagine having to contend with Karinchak's fastball that averages 97 mph and his curveball that gives the illusion of being puppeteered by an invisible string.

After throwing batting practice earlier in the week, Karinchak, the Indians' No. 21 prospect per MLB Pipeline, made his Cactus League debut in Sunday's 9-5 win over the Royals, working a stellar fourth inning in which he retired all three batters he faced. That included freezing slugger Jorge Soler with his breaking ball for a called strikeout.

As far as pitching in Spring Training for the first time -- against Soler, Maikel Franco and Ryan O'Hearn, three hitters who are likely to figure prominently into Kansas City’s lineup -- Karinchak took it all in stride.

“Just helps to build your confidence, I think, just getting some chances out there,” Karinchak said.

Cleveland’s bullpen is slated to return many familiar faces from last season. Karinchak made five big league appearances in 2019, but those came primarily in games that the outcome had already been determined.

But manager Terry Francona simplified the club’s thought process on whether Karinchak would break camp with the Indians this year, saying, “He’s got to be one of the best eight.”

While the Indians had the second-lowest bullpen ERA (3.67) in the Majors last season, no American League squad recorded fewer strikeouts (526) from its relief corps. Believing that Karinchak could replicate his 16.4 strikeouts-per-nine-innings average that he compiled across three Minor League seasons may be a lot to ask immediately, but his power arm could give the Tribe a previously unseen weapon.

As the spring progresses, Karinchak’s control should be one of the Tribe's more intriguing developments. Along with the gaudy strikeout numbers, he has averaged 5.5 walks per nine innings in his Minor League career. He has displayed both swing-and-miss stuff and an inconsistent ability to find the strike zone. Continuing the development of the former while reducing the frequency of the latter is just another piece of his puzzle.

“It won’t just be ERA, things like that. [It will be] stuff, fielding his position, holding runners, things like that,” Francona said.

“I've got to get outs,” Karinchak said.

In addition to knowing that he needs to “cut down the walks," Karinchak mentioned working to improve many of the same intricacies that Francona highlighted.

Primarily a starter during his time at Bryant College, Karinchak made six starts for Class A Short-Season Mahoning Valley in 2017, after he was drafted by the Indians in the ninth round that June. Since then, he has only pitched in relief, which has allowed him to maximize his fastball/curveball mix. No Indians reliever last season averaged higher velocity (97 mph) on their fastball than Karinchak.

Francona made it clear that the right-hander is on the club’s radar for Opening Day against the Tigers.

“His future, we feel, is really bright. Is that on March 26? You know, that’s to be determined,” Francona said.