He's all fastballs before in high school but he has improved his repertoire. His low-90s fastball improved as his body matures, now sitting at low to mid-90s and will reach 100 MPH when he wants to. His fastball has some tail in it but will be flat high in the zone due to the drop and drive nature of his delivery. Even though he threw harder, his feel for his fastball didn't changed and still locates it well. His best secondary pitch is his low to mid-80s slider with massive two plane break. He also got a mid-70s curveball with 12-6 break that can be a tick above average. Both his breaking balls still has inconsistency written all over it and needs more reps but both are promising. His changeup is shaping up to be an average fourth offering.
Pearson has obvious mid-rotation ceiling given his fastball velocity and command as well as the prototypical power pitcher's frame. The key to him is to improve the consistency of his secondary pitches. The Giants might take a shot at him with his obvious ceiling and youth (he's turning 21 in August) and he is rising fast.
You will probably see the 2nd big board of prospects in Scout and here sometime in late-April and possibly a 1st round mock as well in my blog. I hope you enjoy!