Diamondbacks Place Christian Walker On 10-Day IL, Designate Miguel Castro

The Diamondbacks placed Christian Walker on the 10-day injured list earlier today, as the star first baseman is suffering with a left oblique strain.  First baseman Pavin Smith was called up from Triple-A in a corresponding move to Walker’s IL placement, and right-hander Miguel Castro was designated for assignment in another move to create roster space in the wake of Arizona’s deadline-day trades for Josh Bell and Dylan Floro.

Walker left Monday’s game due to what was described as soreness in his left oblique area, and he received some good news today in the form of a relatively positive MRI result.  Walker told reporters (including Nick Piecoro and Jose M. Romero of the Arizona Republic) that his strain was of the minor variety, and he estimated roughly a three-week stint on the IL.

While oblique injuries can linger and a three-week-absence is still a big chunk of the two months remaining in the regular season, it’s obviously a sigh of relief for Walker and the D’Backs and the first baseman’s season doesn’t appear in jeopardy.  The Diamondbacks’ quick move to acquire Bell from the Marlins today was a clear sign that Walker would be missing some significant length of time, but if Walker is indeed able to return in three weeks’ time, Bell will become an interesting backup or part-time DH option to bolster Arizona’s bench.

Landing Bell and recalling Smith are stopgap options for the Diamondbacks, as there’s no way to truly replace Walker’s all-around contributions.  In addition to being arguably the game’s best defensive first baseman, he has been a consistent force at the plate, including his 23 home runs and .254/.338/.476 slash line in 461 plate appearances this season.  With the Snakes in a pitched battle for a wild card spot, they’ll face an extra challenge in trying to stay afloat while missing one of their top players for the better part of August.

Castro has a 5.93 ERA over 13 2/3 innings and only 11 appearances this season, as the righty just returned to action just prior to the All-Star break after missing close to three months on the injured list due to shoulder inflammation.  It is safe to say his injury impacted his performance, yet with the D’Backs bringing new bullpen arms into the fold, Castro is now the odd man out.

Castro signed a free agent contract with Arizona during the 2022-23 offseason that paid him a guaranteed $3.5MM salary for 2023, and carried a $5MM vesting option for 2024 which triggered if Castro appeared in at least 60 games last season and passed a season-ending physical.  He easily locked in that extra year with 75 appearances, tossing 64 2/3 innings in a workhorse role out of the bullpen and posting a 4.31 ERA.

If Castro is claimed on waivers, a new team will assume the remaining $1.6MM or so remaining of his 2024 salary, which probably isn’t too likely given his lack of production.  Should he clear waivers, Castro has enough MLB service time to reject an outright assignment to the minors and instead opt for free agency.