Mariners 40-man Pitchers to watch
Isaiah Campbell (25 Years old - RH Reliever) is a converted starter, much like many think is going to be the case with the next guy on the list. After switching it up, Campbell found a ton of success in the bullpen in 2022. He's joined the MLB group in featuring a slider as a strong part of his arsenal and saw an incredible strikeout rate of 11.5, but 16.6 in AA in 13 innings.
Those 13 innings are the only ones Campbell has seen at AA or higher, but the expectation is still high with him to get a shot in 2023 with the Mariners. He's going to get a good look alongside Sadler and some of the other MLB relievers fighting for a spot, and a good opportunity to throw in a bunch of Spring Training games.
Prelander Berroa (22 Years old - RH Starter currently) was acquired by the Mariners in 2022 in exchange for UTIL Donovan Walton (miss that guy). Originally barely on the top 30 prospects list, Berroa has skyrocketed since coming to Seattle. He has electric stuff but massive control issues, walking more batters (63) than allowing hits (54) in his 100.2 IP in 2022.
The control is a big reason that he might turn into a reliever. With a fastball in the mid to upper 90s that can actually touch 102 and a devastating plus-plus slider that touches 90 mph, the stuff is NSFW disgusting. Harnessing that for an inning or two could be the way to success, and seeing what the Mariners do with him in ST should be telling.