Jonatan Clase

Clase had an impressive pro debut as a 17-year-old in the Dominican Summer League in 2019, hitting .300/.434/.444 (147 wRC+) with two home runs and 31 steals (on 41 attempts) in 63 games. He was dealing with an undisclosed injury during most of the fall instructional league in 2020, but the Mariners say he was able to hit and that his hit tool and power appear to be real. That power is a new and important development. Clase, who was listed at 5-foot-8, 150 pounds when he signed in 2018, was listed at 6-foot, 200 pounds at instructs. He is the fastest player in Seattle's farm system (at least a plus runner), and now it seems that Clase is has a chance to be a five-category fantasy contributor. Since we're still awaiting his official stateside debut, it's hard to say exactly where his offensive skills are now, but he has the physical tools to jump 100 spots on the prospect rankings this season.