On Friday, the Tampa Bay Rays acquired right-hander Robert Stephenson from the Pirates as a means to start addressing a thin bullpen. Minor league shortstop Alika Williams is heading to Pittsburgh in return. To create space on the 40-man roster for Stephenson, the Rays designated RHP Ben Heller for assignment, although another move is expected to create space on the 26-man roster when Stephenson is activated.
Stephenson began his career as a starting pitcher in Cincinnati yet, over the years, he has been converted to a reliever. After posting a 3.76 ERA and a 3.63 FIP, with a 1.04 WHIP, and a 3.38 K/BB over 57 appearances in 2019, his first full season in the bullpen, things began to go sideways for the hurler. In the truncated 2020 season, Stephenson’s ERA shot up to 9.26 across 10 appearances with the Rockies.
Stephenson bounced back with a solid 2021 campaign in Denver, putting up a 3.13 ERA and a 3.63 FIP before he struggled again in 2022 when he performed to a 6.04 ERA through August before he was designated for assignment. The Pirates picked him up, and he was able to finish on a high note, posting a 3.38 ERA in 10 outings with Pittsburgh down the stretch. He ended the ’22 campaign by lowering his ERA and FIP to 5.43 and 4.23 FIP (respectively).
That brings us to this season…
Stephenson began 2023 on the Injured List with elbow inflammation and returned in the middle of April. In 18 appearances since his return, the right-hander has a 5.14 ERA and a 5.26 FIP, a 1.43 WHIP, a 5.14 BB/9, and a 2.13 K/BB. On the positive end of things, Stephenson has struck out 27.9% of opponents this season, but, on the other hand, he’s walked 13.1% of batters. Take this with a grain of salt given the small 14.0-inning sample size.
Stephenson relies primarily on a whiffy 85 mph slider (generating a 43.2% whiff rate) that he throws 65% of the time and boasts a lot of movement, and a 97 mph fourseam fastball that has arm-side run — his heater has been hit hard this season — while also mixing in a hard 89 mph split-finger changeup. In some regards, the Rays may view him as a Matt Wisler type of pitcher with a more lively arm. Then again, given that his fastball averages over 21 inches of total movement (both horizontal and vertical movement), but he’s only thrown the pitch in the upper third of the zone a very small percentage of the time, it’s possible that they could work toward getting him to pitch at the top of the zone more often to coax more whiffs or weak pop-ups.
Kyle Snyder and the Rays will take a shot at helping him turn things around. And I f nothing comes of it? Stephenson will end up being a short-term piece since he will hit free agency at the end of the season.