Selected by the Athletics in the fifth round of the 2014 draft, Fillmyer was traded to Kansas City in January 2018 as part of the deal that sent Ryan Buchter to Oakland. He made his MLB debut that summer and picked up 17 appearances (13 starts) down the stretch. He posted a 4.26 ERA but punched out a below-average 16.6% of opposing hitters. Fillmyer was hit hard over 22.1 innings in 2019 and wound up losing his spot on the Royals’ 40-man roster following that season. While he was part of Kansas City’s 60-man player pool last year, the 26-year-old didn’t return to the majors.
Fillmyer has managed a 5.07 ERA/5.10 SIERA over 104.2 MLB innings. He has struggled to miss bats (career 15.9% strikeout percentage) but he’s induced ground balls at a decent clip (45.3%) and avoided walks at a near-average rate (9.7%). Fillmyer posted quality numbers up through Double-A and gives the D-Backs a depth option capable of either starting or working multiple innings in relief.