Mariners Draft Profile: Oklahoma State RHP Justin Campbell
Standing at 6-foot-7, 220 pounds, Oklahoma State right-handed pitcher Justin Campbell is very intimidating on the mound. His height helps him deceive hitters; many struggle to pick up the baseball with his long extension.
At Oklahoma State this year, Campbell pitched 101.1 innings with 141 strikeouts and only 25 walks to help compose a 3.82 ERA. He struggled with home runs this season (allowing 15), but those issues have not been prevalent in the past. He is a Mariners-style pitcher; he pounds the zone, gets a lot of whiffs and has a decent batted ball profile. He has a lot of similarities to Seattle's 2018 first-round draft pick Logan Gilbert.
Let me start with the caveat: Campbell has not tapped into his velocity yet. While his extension and size allow his fastball to play up a little bit, it still only averages 91.5 MPH on the radar gun. This is an issue with his off-speed pitches as well. While he could certainly add more weight to his frame to help increase his velocity, he also might need a mechanical overhaul. His current delivery is not conducive to high velocity because he has a poor load and does not rotate well.
Being a tall guy, Campbell is somewhat stiff, so these mechanical adjustments may be difficult to implement. Seattle's player development is notorious for its annual "Dominate the Zone" pitching camp (formerly known as "Gas Camp") and has demonstrated overwhelming success. The organization knows how to develop velocity and could feel confident in its ability to help Campbell.
Campbell actually has very good data on his individual pitches. The fastball has elite movement, with an average induced vertical break of 20.9 inches. This shaping is nearly fully optimized to miss bats already. His changeup is also a great pitch. The 12 MPH difference between his fastball and changeup is suboptimal, but the spin rates and movement on the pitch are elite. The IVB is 20 inches again, but the horizontal break has an average of 17.7 inches of movement. He can locate it and throw it for strikes. While it is already a good pitch, teams would be salivating if Campbell added velocity to his changeup so it complemented his fastball better. It is very encouraging that the changeup performs this well despite this issue.
His slider is probably his worst pitch and projects as fringe. It has issues with its movement, shape and velocity, and it does not result in a lot of whiffs or chases. His curveball has phenomenal vertical movement but it can be easy to pick up for a batter since it currently sits at 76 MPH. If Campbell could add roughly five MPH of velocity to all of his pitches, he would be the best arm in this class. This is similar to what publications and scouts said about Angels' lefty Reid Detmers when he was coming out of the draft in 2020, and he tore up the minor leagues after adding significant velocity to his entire repertoire, including his nasty curveball.
If Campbell was a pitcher who averaged 95 MPH on his fastball, he would probably be taken a lot earlier in the draft than he is currently being projected. I would be surprised if he is taken before pick No. 20 in the draft, so he should be available for Seattle if it wants him.
