Diamondbacks release Max Kepler after DFA; free agency expected to follow

Max Kepler's brief run in Arizona is over. The Diamondbacks released the outfielder on September 8, per the MLB.com transaction log, days after designating him for assignment and recalling catcher Adrian Del Castillo from Triple-A Reno. Per Connor Byrne at MLB Trade Rumors, the release was the expected outcome once the DFA was issued.

What happened

The Diamondbacks announced the designation of Kepler and the corresponding recall of Del Castillo from Triple-A Reno, leaving the club with two open spots on its 40-man roster. The release followed within days, per the MLB.com transaction log. Because Kepler has accumulated more than enough service time to reject an outright assignment, he is expected to clear waivers and elect free agency, per Byrne. With the Triple-A season winding down in the coming weeks, Byrne notes there is a reasonable chance Kepler remains unsigned until the offseason.

Why it matters

The Kepler signing was always a calculated flier. Arizona gave him a major league deal worth a prorated $780K after he went unsigned until early June — a delay that itself followed an 80-game PED suspension that kept him off the field to start the season. The Diamondbacks activated him on June 25, and over 41 games and 145 plate appearances, the results never arrived.

His .205/.262/.303 line, a 53 wRC+, and a career-worst .098 ISO told a consistent story: the bat that had made Kepler a useful piece for years in Minnesota was not showing up in Arizona. The club did what it could to manage the situation, shielding the left-handed hitter from same-handed pitchers — he faced lefties just 12 times before the designation — but even against righties, who had historically been a relative strength, Kepler posted a .192/.256/.283 line (47 wRC+) during his time with the club. All 35 of his defensive starts came in left field.

The DFA and subsequent release close a chapter that, operationally, had already been written. The roster spot now belongs to Del Castillo, and Arizona moves forward with Ryan Waldschmidt and Lars Nootbaar — the trade deadline addition — as the primary options in left field over the final weeks of the regular season.

The numbers

Kepler's season line with Arizona: .205/.262/.303, 53 wRC+, .098 ISO, 2 home runs across 145 plate appearances. Against right-handed pitching, the matchup the club leaned into, he managed a .192/.256/.283 line and a 47 wRC+.

Zoom out and the recent arc is difficult to ignore. Since 2024, Kepler has totaled 1.0 fWAR across a combined 1,018 plate appearances with the Twins, Phillies, and Diamondbacks. The previous season with Philadelphia — .216/.300/.391, 88 wRC+, 18 home runs in 474 plate appearances — now looks like the high-water mark of a difficult stretch. For context on how far the production has traveled: Kepler's best season came in 2019, when he posted 3.9 fWAR and hit 36 home runs for the Twins team that set the all-time single-season home run record at 307 — a mark the 2023 Braves later tied. He totaled 2.7 fWAR and 24 home runs with Minnesota as recently as 2023, but the trajectory since then has been a steady decline.

Where the club stands

None of this lands as a crisis for Arizona. The Diamondbacks enter the week at 78-68 (.534), sitting second in the NL West and riding a four-game winning streak. They hold a position in the Wild Card race that makes every roster decision between now and the end of the regular season meaningful — and the Kepler DFA is one of them.

The upcoming schedule includes a Wednesday game at Kauffman Stadium against the Kansas City Royals, followed by a home series against the Texas Rangers on Friday and Saturday at Chase Field.

What we don't know yet

### Will Kepler find a roster spot before the offseason?

Per Byrne, probably not immediately. With the Triple-A season ending in the coming weeks, the market for a veteran outfielder clearing waivers in September is narrow. The expectation, per the reporting, is that Kepler's next contract — if one comes — will be negotiated this winter.

What the Diamondbacks do with the two open 40-man spots beyond the Del Castillo recall also remains to be seen. September rosters expand to 28 players under current rules, and clubs typically use that flexibility to add depth from the upper minors.

What to watch

Arizona's outfield picture over the final weeks is worth monitoring. Waldschmidt and Nootbaar are the names Byrne identifies as the primary left-field options in recent weeks, and how the club deploys them — particularly Nootbaar, who arrived at the trade deadline — will shape the roster's look heading into any potential postseason.

The broader Diamondbacks context is also worth keeping in mind. A day after the Kepler release, Corbin Burnes made his 2026 season debut against the Royals, returning from Tommy John surgery and delivering three scoreless innings, per earlier Posterior Wire reporting. Zac Gallen was also reported to be targeting a return from the 60-day IL for that same series. Geraldo Perdomo, who exited a game after taking a line drive off his helmet, has since returned to the lineup. The club is navigating a compressed, consequential stretch with a roster that looks meaningfully different than it did even a week ago — and the Kepler departure is one of the quieter threads in what has been a busy few days in the desert.

For Kepler, 33, the path forward is less clear. A player whose best seasons are now several years in the rearview, whose most recent extended look produced a 53 wRC+ and a career-worst ISO, will need to find a club willing to bet on a rebound. That conversation, per the reporting, is likely an offseason one.