Hisashi Iwakuma Sidelined For Five Months After Arthroscopic Shoulder Surgery

Hisashi Iwakuma underwent arthroscopic right shoulder debridement surgery two days ago, as per an announcement from the Mariners.  The right-hander is expected to resume throwing in five months, putting him on pace to miss the first few weeks of Spring Training and likely to miss some time at the start of the season as he rebuilds his strength.

Iwakuma made just six starts for the M’s in 2017 before being sent to the disabled list with inflammation in his throwing shoulder.  What was expected to be an absence of four-to-six weeks ended up lasting the entire season, as Iwakuma suffered a setback that couldn’t be overcome despite cortisone and PRP injections.

It was already expected that Seattle wouldn’t exercise their $10MM club option on Iwakuma’s services for 2018, and the veteran righty will instead receive a $1MM buyout.  It isn’t out of the question that the Mariners re-sign Iwakuma to a smaller or even a minor league contract for next season in the aftermath of his surgery — they’re obviously more familiar with his health situation than other teams, who would naturally be wary of adding a pitcher who turns 37 in April and will probably need significant time to ramp up for action in 2018.

Never a hard-thrower or a big strikeout pitcher, Iwakuma has relied on a recipe of grounders, soft contact and a lack of walks over his six MLB seasons, all with the Mariners.  He was seemingly on the verge of signing a three-year, $45MM deal to join the Dodgers in the 2015-16 offseason before L.A. pulled out of that agreement due to a still-unknown concern with Iwakuma’s medicals.  Iwakuma returned to Seattle on a one-year contract that contained a pair of vesting option years, the first of which Iwakuma caused to vest for 2017 by easily surpassing the 162-inning threshold (he tossed 199 frames in 2016) and finishing the year injury-free.

Starting pitching is a clear need for the Mariners this offseason in the wake of all their rotation injuries this year.  James Paxton, Felix Hernandez and Mike Leake have three spots spoken for and the M’s have several young arms who could battle for at least one of the other rotation jobs, though adding a reliable veteran would greatly help stabilize the Mariners’ staff.