Mariners have loved Gilbert since his stellar 2017 Cape Cod League performance, but his fastball velocity was down a few ticks since then. Will need to sharpen and have more confidence in his secondary offerings as he moves up the ladder. Feel for pitching and repeatable mechanics give him a shot as a big-league rotation piece, but right now it’s hard to see Gilbert as more than a backend starter. However, if the velocity comes back and the secondaries improve, there is some upside.