Two refined pitches helped turn Gerrit Cole into the Yankees’ $324 million man.

Cole already was an All-Star pitcher in 2015 with the Pirates, but after an increased usage of his four-seam fastball — and specifically throwing it up in the zone more — and a minor tweak to his changeup grip, with a tip from a Hall of Famer, Cole enters 2020 as one of the best arms in the game and the Yankees’ new ace, whenever MLB returns to action.

“Yeah, it initially started in 2017 when I found that I was really inefficient when I was trying to throw strikes with the sinker, and sometimes it would slide off the plate or it would break too much, and I was really just trying to get count leverage in a lot of those situations, so I started mixing more four-seamers in,” Cole told YES Network’s Jack Curry and David Cone during spring training for a special episode of “Yankees Access: Cole, Cone & Curry,” which is set to premiere Monday at 7:30 p.m.

“When I got to Houston, you know, [pitching coach] Brent Strom was just such a great resource to the 70’s and 80’s, and maybe even late 60’s kind of style of Don Sutton, Tom Seaver, Drysdale, top of the zone kind of fastball, and he just, you know, he just encouraged me to chase that type of pitching.

“Ironically, throwing the four-seam more was easier for me. It was just, made my breaking balls more consistent and I found that even if you still locate the four-seam at the bottom of the zone, you’re still apt to get a groundball in those situations. So, it cost me less, it made me more efficient because I could put guys away when I wanted to, instead of trying to induce contact and hoping that it didn’t go to somebody.”

In five seasons with the Pirates, Cole posted a 3.50 ERA with 734 strikeouts and 203 walks in 782 ¹/₃ innings. After he was traded to the Astros in January of 2018, Cole took his game to another level and cut his ERA down to 2.68 with 602 strikeouts and 112 walks in 412 ²/₃ innings over the last two seasons in Houston.

After throwing his four-seam fastball on 47.3 percent of his pitches as a Pirate, per Brooks Baseball, Cole threw it for 53.79 percent of his pitches as an Astro. The swing-and-miss rate on those four-seamers went way up with the increased usage and throwing it at the top of the zone — from 9.07 in 2017 to 15.20 in 2018 and 18.35 in 2019.

The second pitch that was key to Cole’s improvement was his changeup, which Nolan Ryan helped with in Houston.

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“Well, Justin (Verlander) and I were talking to Nolan one day and we were showing him both of our changeup grips and I was just kind of asking, saying kind of, I would like to get a little more depth out of my changeup,” Cole told Curry and Cone. “He was asking me about my grip and he saw that I really put my middle finger, kind of right through the center of the ball and thought that the middle finger, at least for him, was the finger that generated, kind of, the most power and the index finger kind of steered the ball. So, he suggested, kind of what he did, which is where he offset the middle finger a little bit more to the inside of the ball so that he didn’t quite get so much power coming through the pitch. But, you can still finish the ball with good snap, like you do on your fastball.”

The results showed. Batters had more difficulty hitting Cole’s changeup when he was an Astro. The pitch induced a 11.76 whiff rate when he was with the Pirates and opposing batters hit .266 against it, per Brooks Baseball. With the Astros, Cole’s changeup induced a 16.63 whiff rate and a .200 batting average against.

“I thought it helped,” Cole said. “It certainly gave me more confidence to throw the pitch aggressively over the plate, ‘cause I did notice that the velocity was more consistent, and as long as I got through the baseball, like I got through the baseball in my hand, or out of my fastball rather, I got an early commit to the pitch. So, it wasn’t always, it had a good chance of having some success.”