Regardless, coaches and teammates have raved about Garcia, the son of a doctor and a baseball trainer. He has been imperturbable on the mound and shown a curiosity to improve off it, from sharpening his already solid English to perfecting his craft.

“I’ll tell you what’s impressive for his age: his makeup, his poise, his competitiveness, and what I’m learning, his aptitude,” said Tommy Phelps, the RailRiders pitching coach. “He’s able to make adjustments and understand what he’s doing.”

Behind home plate during a recent start was the best vantage point to see how Garcia fooled opposing batters despite his limited velocity and his size, which he joked wasn’t intimidating anyone. As he wound up to throw, Garcia twisted, angled his back toward home plate and dropped his arm behind his body, hiding the ball from the hitter. The ball reappeared, with a quick whip of his arm, at the last moment before being released.

Some coaches have tried minor adjustments to Garcia’s delivery, but he said that this was his natural way of throwing. It helped Garcia that his fastball possessed above-average spin and fooled batters into thinking the ball was rising, which induced swings and misses even with velocity in the low 90s. Garcia is able to slip his fastball by batters because it appears faster, Phelps said, thanks to his ability to release the ball closer to the plate than a hitter might expect of a pitcher his size. “It’s sneaky,” Phelps said.

The Yankees so coveted Garcia that they resisted dealing him for pitching help at the trading deadline, even though they had said publicly that their staff was a weakness. As a result, there was more pressure to improve from within. They banked on starter Luis Severino and reliever Dellin Betances to return from injuries in September, but also on the potential call-up of Garcia, who could be eased into the major leagues by working out of the bullpen, like other top pitching prospects.

A signal that his call could come soon is that Yankees minor-league coaches have been careful with Garcia’s pitch counts all season; he was recently moved to the RailRiders’ bullpen because he had never thrown as many innings in a season as he did this year. But the switch had an added benefit: It served to audition him for a September in pinstripes.