The real career ERA leader for the Seattle Mariners
#3: Hisashi Iwakuma: Innings Pitched: 883.2, Earned Runs: 336, 3.422105 ERA
This one surprised me a bit. I think Iwakuma might actually go down as one of the most underrated players to ever be on the Mariners. He was the first miss on the best contracts handed out by the Mariners this millennia. Setting aside his best season, which I’ll get to in a minute, he was extremely consistent the rest of his time in Seattle. He had a 2.3, 2.4, 2.6, and a 2.4 WAR in four of his first five seasons with the team.
If you can get a stretch like that from anyone other than your ace, you’ve got a darn good pitcher on your hands.
After starting the season in the pen for the Mariners his rookie year, Iwakuma moved to the rotation halfway through the season and never looked back. That first full season as a starter in 2013 was special, and a big part of the reason that Iwakuma is tied for the career ERA lead on the Mariners.
He made every start that season, throwing 219.2 innings across 33 starts. Anytime you can get 6.2 innings from your starter on average, you know you’ve got a good one. The 2.66 ERA was super impressive, as was the 1.006 WHIP. He even led all American League Pitchers in WAR, beating out Cy-Young winner Maz Scherzer, who had a 6.5 compared to Iwakumas 7.0.
The hope was the Mariners could strike gold again with another international signing when they brought on Kikuchi. Instead, he ended up as one of the worst deals the Mariners ever signed.