PITTSBURGH -- When rehabbing with Triple-A Indianapolis last month, Yasmani Grandal got a chance to catch Paul Skenes and see his stuff first-hand. Much has been written about the right-handed phenom’s triple-digit fastball and wipeout slider, the two pitches he rode to the heights of the College World Series with LSU last year that established him as perhaps the greatest pitching prospect of his generation. Never hurts to be able to see that in-person.

But when Skenes arrived to Pirate City in Bradenton, Fla., this spring, he made clear that he wanted to use his full pitch arsenal. That included a curveball, a changeup and a hybrid pitch between a splitter and sinker, which he referred to as a “splinker.” (For the purposes of pitch tracking, this pitch is classified as a splitter on scoreboards and leaderboards. The same goes for Twins closer Jhoan Duran, another notable "splinker" artist.)

Reporting back to Derek Shelton about that splinker, Grandal spoke highly, telling his manager “this pitch is different.”

The Cubs saw that third pitch plenty during Skenes’ debut Saturday, and it was arguably his most effective pitch. His fastball was a bit more wild than usual, something Shelton attributed to the adrenaline of the day. The slider didn’t break as consistently, but still landed for called strikes, even if it’s not how Grandal drew it up.

• Livvy Dunne chimes in on boyfriend Paul Skenes' MLB debut

But the splinker? The Cubs swung at it 12 times Saturday and whiffed five times, which included a punchout of Yan Gomes to end the fourth. Grandal called for it often, too, with Skenes throwing it 21 times in his 84-pitch outing.

“It was working good,” assessed Grandal. “Definitely diving.”

Since the advent of pitch tracking in 2008, only nine pitchers have ever thrown a splitter 95 mph or harder. Skenes is one of them, averaging 94.7 mph yesterday.

“You don’t see anybody throw it at 95, 96,” said Shelton.

That’s part of what makes it an effective hybrid pitch. It has the extra velocity of a fastball, and the movement profile of a splitter, getting more vertical bite.

In terms of movement, it profiles very similarly to Zack Wheeler’s splitter: 31.8 inches of vertical movement for Wheeler, 31.4 for Skenes, with 13.4 inches of horizontal movement for Wheeler and 13.8 for Skenes. Wheeler’s splitter is among the top in the sport in terms of run value. The difference is Wheeler’s splitter averages 85.4 mph compared to 94.7 mph for Skenes. Only the Angels’ José Soriano can match Skenes’ velocity and movement on the pitch.

When asked postgame if he had ever seen a pitch like that, David Bednar -- who himself has earned two All-Star nods in part due to his splitter -- chuckled and said, “No, not quite.”

“He’s very special on the mound out there, man,” Bednar said. “A lot of stuff he can do with the baseball that’s really impressive.”

Skenes didn’t feel he could throw the pitch much at LSU, but in pro ball, the focus has been more on refining it, finding good opportunities to use it and getting reps rather than trying to find a pitch shape.

“It's just been throwing it,” said Skenes. “That's the only work I've had to do on it. The shape's always been there, just learning how to pitch with it.”

It’s another example of why Skenes is effective beyond just his pitch velocity. General manager Ben Cherington said before Saturday’s game that he believes Skenes has improved as a pitcher over the past year, even after he reached the dizzying heights after the College World Series.

“We thought he'd get better over time, obviously, but to do that in a relatively short time is impressive,” said Cherington. “These things are not easy. These things he's trying to do are not easy. His pitches are different. The way he attacks hitters is different from a year ago. He's become a better pitcher in a relatively short amount of time.”

Time will tell how this pitch will continue to play, but the splinker could be proof of Skenes continuing to improve and potentially fulfill the massive hype surrounding him.