LAKELAND, Fla. -- Casey Mize combines stuff and polish better than any pitcher to come out of the Draft since Stephen Strasburg. The Nationals used the No. 1 overall pick in 2009 on Strasburg, considered the best pitching prospect in Draft history, and the Tigers did the same last June on Mize.

With three pitches that grade as plus or better, Mize led NCAA Division I with a 12.1 strikeout-to-walk ratio as an Auburn sophomore in 2017 and placed fifth last spring with a 9.8 mark. Detroit limited him to 13 2/3 innings last summer after signing him for $7.5 million, but it plans on turning him loose this season, likely starting him in Class A Advanced.

• Tigers' prospects at Spring Training | Tigers Top 30

Mize says he has no destination goals for 2019, focusing instead on how he prepares and performs. He's trying to refine a new pitch and his already advanced command while getting acclimated to a five-day rotation after working once a week in college.

"Last summer, that was the biggest thing for me, and it was a very small sample size," Mize said. "I only threw three innings at a time and I was sore, I was dragging. That was probably the most positive thing about pitching last summer because this offseason, I trained for that.

"My throwing days were based on a five-day rotation so I could get my arm and my body used to that quick turnaround. Doing that on a much larger scale now, throwing 100 pitches and going to throw 100 pitches again five days later is something I need to develop the ability to do that well."

When MLB Pipeline spoke with Mize during Spring Training, he broke down his entire repertoire and demonstrated his pitch grips. He throws two- and four-seam fastballs, a slider/cutter, a slurve and a split-finger fastball. We asked him to rank his pitches in order of effectiveness.

"I'd probably say fastball one because I can command it pretty well," Mize said. "Split would be two because it's my best offspeed offering. Cutter would be three right now, just because it's something I can throw in a hitter's count for a strike to get them off the fastball.

"And the slurve right now would be four, which I think is going to move up pretty quickly. I think in the past, my slider, my breaking ball has always been my fourth-best pitch, something I can throw early in counts. I think the slurve is something that I'll be able to throw late in counts as a strikeout pitch now."

Mize uses conventional grips on his two- and four-seam fastballs, usually ranging from 92-97 mph. He gets sink on his two-seamer and riding action on his four-seamer, commanding both exceptionally well. He estimates that he throws the two versions of his fastball an equal amount, using the two-seamer to his arm side (in on right-handers, away from left-handers) and the four-seamer to his glove side (in on lefties, away from righties).

Mize's split-finger is more devastating than his fastball and might have been the single best offering in the 2018 Draft. He throws it at 85-89 mph and it plummets at the plate, but what makes it truly special is his ability to locate it. Hitters can't just lay off his splitter and expect it to dive out of the strike zone, because he commands it better than most pitchers can.

Mize said he began using a splitter in high school after he fell in love with his slider, lost his feel for a changeup and needed an alternative. He initially threw the pitch with his index and middle fingers centered between the seams and continued to do so in his first year in college. When Auburn coach Butch Thompson suggested he try using his index finger to pull on the seam on the left side of the ball and have his middle finger split the horseshoe shape on the other side of the ball, a weapon was born.

"I tried that and I was able to command it better, throw it harder, all of the above," Mize said. "It had more run and more sink. I've just been throwing it like that ever since.

"Sometimes it's spiking or sailing here and there, but I'm never going to give up on the split because it matches with the two-seam fastball so well and they have similar spin. I need that pitch to be on, to honestly be successful. If I don't have a feel for it that game, I'm going to keep throwing it."

Entering his junior year at Auburn, Mize was unsatisfied with a slider that wasn't as hard or as tight as he wanted. Ten days before the season began, he explained to graduate assistant coach Tyler Stovall (a former Braves second-round pick) that he wanted to release the pitch like a football and have it spin like a bullet. Stovall commented that what Mize was describing sounded a lot like a cutter and showed him how to throw one.

"He showed me that grip and I threw it and it was spinning like a bullet, everything I want, and it was 88-90 [mph]," Mize said. "It's exactly what I wanted. So I called that a cutter. By definition of its spin, it's technically a slider, but mentally I have to think 'cutter' to throw it harder."

Even after going No. 1 overall and signing for the highest bonus in the Draft pool era, Mize sought to add to his arsenal. He wanted a sharper, more traditional breaking ball and experimented with grips and analyzed spin with Edgertronic cameras and Rapsodo radar during the offseason at a Brentwood, Tenn., facility run by his representatives, The Bledsoe Agency.

Caleb Cotham, then The Bledsoe Agency's director of pitching and now an assistant pitching coach for the Reds, advised Mize to spike his index finger on one seam and use his middle finger to pull down on the opposite seam. He's excited about his new mid-80s slurve.

"He showed me that grip after I had tried out a few and this one, it was spinning really well," Mize said. "I really like the shape of the pitch and how it was spinning. ... The slurve is something I've worked on all offseason, so I want to put that in a game and see that be successful. That's going to be big."