The Diamondbacks made a small but telling move on the pitching staff Sunday, selecting the contract of right-hander Dennis Santana from Reno while designating Philip Abner for assignment. It's the kind of transaction that barely registers outside the box score, but it says a lot about how Arizona is treating the last six weeks of the season: nothing is settled, and every bullpen arm is auditioning.
Santana is no stranger to bouncing between organizations. The 30-year-old is joining his sixth big-league club after stints with the Dodgers, Rangers, Mets, Yankees and, most recently, the Pirates. He'd actually been dominant in Pittsburgh's bullpen in 2024 and 2025, posting a 2.44 ERA and then a 2.18 ERA, but a rough 2026 season sank him — a 6.05 ERA in 41 2/3 innings led the Pirates to designate him for assignment in late July before releasing him outright. Arizona scooped him up on a minor league deal on August 6th, and it took barely a week and a half for him to force his way back to the majors.
Abner's path has been the opposite. Arizona's sixth-round pick in the 2023 draft, the 24-year-old lefty had shown real promise in the minors, running a 3.07 ERA last year with strong strikeout and walk numbers. But his first real taste of the big leagues went sideways — an 6.28 ERA over 14 1/3 innings in eight appearances, with more walks than strikeouts, and a 5.01 ERA back at Reno didn't help his case either. If he clears waivers, he'll have to accept an outright assignment before Arizona — or anyone else — could bring him back up.
None of this is happening in a vacuum. Arizona is currently sitting on a Wild Card spot and has been one of the hottest teams in the National League since the middle of July, and the bullpen has largely carried its share of the load during that stretch. Adding a veteran arm with a track record of missing bats, even one coming off a down year, is a low-cost bet with real upside if Santana can rediscover the form that made him a shutdown reliever for two straight seasons in Pittsburgh.
For Abner, it's a tough break after such a short big-league runway, but it's also a reminder of how unforgiving roster math gets in a playoff race. Arizona doesn't have the luxury of letting a young arm work through growing pains when every relief appearance in August and September could swing a game that decides a postseason spot. Whether Santana sticks around past this stretch or Abner finds his way back once he's had time to reset in the minors, this is the kind of churn that's going to keep happening on the D-backs' pitching staff right up until the roster locks in for October.