During a pitch development presentation in 2019, Orioles pitching coach Chris Holt started a video for the minor leaguers present. The film displayed some of the best changeups in baseball, with the highest spin rates, from Luis Castillo, Devin Williams and others.

Grayson Rodriguez watched and took note of how the circle-change grip from both of those pitchers could be augmented by hand positioning. Rodriguez had tested a changeup the offseason prior with Josh Tomlin, a former major leaguer pitcher with whom Rodriguez trains in Texas.

But after seeing the film, Rodriguez had a better understanding of what a changeup could be — and how it could elevate his arsenal. Two days later, as Holt walked past a throwing program, the top prospect called for his coach’s attention.

“Hey,” Holt remembers Rodriguez telling him, “I think I figured out that changeup thing you were showing me.”

In the span of two days, Rodriguez added the new pitch to his repertoire. And while there’s no such thing as perfection — Rodriguez still tinkers from start-to-start with all his offerings — his changeup has developed into his most lethal offering.

The eyes can gravitate toward his high-velocity four-seam fastball, a pitch that has 97% spin efficiency leading to movement. But when Rodriguez plays a changeup off that heater, it creates a devastating pairing, one that is 15 mph slower than the other and dips when the other runs, yet looks the same coming out of his hand.

Holt could see the potential of that changeup just two days after he introduced Rodriguez and a room full of prospects to video of the best changeups in the game.

“The next outing he had, he was throwing a changeup we’ve never seen from him before,” Holt said. “He just watched it and went, ‘I think I can do that.’”

Now, the 23-year-old’s changeup is rising in reputation, just as the arm that releases it establishes him in the major leagues with Baltimore. As Rodriguez becomes more comfortable on the mound for the Orioles, the club’s top pitching prospect’s belief in that pitch led to his best outing yet last week and holds the key to future success.

In Rodriguez’s first two starts, he felt his changeup came out flat. It didn’t have the spin or movement that eludes bats, instead hanging up in the zone. While slower than his fastball, that lack of movement allowed hitters to adjust.

Rodriguez threw his changeup 32 times against the Texas Rangers and Oakland Athletics. Opposing hitters swung at it 20 times. And only thrice did they miss.

“There wasn’t much depth on it,” Rodriguez said. “It was just staying up in the zone, and obviously those are easy to hit. Not missing many barrels with it.”

But after focusing primarily on that pitch last week during his throwing and bullpen sessions, Rodriguez felt his confidence grow in it again. He didn’t change his grip, but adjusted his hand positioning slightly — that is, the grip stays the same, but by moving the ball slightly his fingers could manipulate the ball based on the seams in a more effective manner.

The change was seen immediately. Even when he allowed four runs in the first inning Sunday against the Chicago White Sox, his first strikeout in that inning against Eloy Jiménez came against his changeup.

Rodriguez wound up leaning heavily on that pitch, throwing it 27 times against the White Sox. His spin rate rose 54 revolutions per minute on average, raising his season’s active spin rate to 83% on the changeup. And while Chicago’s hitters swung at 17 of the 27 changeups he threw, they whiffed at eight of them — nearly half. Rodriguez recorded six of his eight punchouts with his changeup.

After allowing four runs in the first, Rodriguez pitched four scoreless innings, displaying a command befitting of his prospect stature.

“It opens the door to everything. It gets guys off the fastball and really, if you’re able to mix speeds well, it just kind of keeps balls off the barrel,” Rodriguez said. “Just being able to know you can throw it in pretty much any count, it’s a real confidence booster.”

To get to this point with that pitch, Rodriguez studied his changeup usage on slow-motion videos and on TrackMan technology with Orioles minor league pitching coach Justin Ramsey in 2019. He skipped a start to work with Ramsey on his changeup, and while that process might’ve taken months, Rodriguez showed an aptitude far ahead of many pitchers.

Holt had seen that aptitude even earlier, when Rodriguez called him over just two days after being exposed to video of the best changeups in the game. Now it’s Rodriguez’s changeup that could soon find its way into the next batch of examples.