The Marlins announced Wednesday that they’ve selected the contract of righty Seth Martinez from Triple-A Jacksonville and placed fellow righty Janson Junk on the 15-day injured list due to ulnar nerve irritation in his right arm. Miami also recalled right-hander Freddy Tarnok from Jacksonville and optioned lefty Josh Simpson to Triple-A in his place. The Fish already had an open spot on the 40-man roster, so a corresponding 40-man move for Martinez wasn’t necessary.
The call back to the big leagues is a nice early birthday present for Martinez, who’ll turn 31 on Friday. The Arizona State product has pitched in parts of four major league seasons, all with the Astros, for whom he suited up in 2021-24. Martinez has 137 1/3 innings at the big league level in his career, during which he’s produced a 3.93 ERA (4.24 FIP, 4.19 SIERA) with a 20.7% strikeout rate, a 9.2% walk rate and a 39.6% ground-ball rate.
Martinez came to the Marlins via waivers at the end of a tumultuous offseason. Houston placed him on waivers back in November, setting off a string of transactions that sent him from the D-backs, to the Marlins, to the Mariners and back to Miami over a span of four months. The Fish finally succeeded at passing Martinez through waivers at the end of spring training, and he’s spent the entire year with their top affiliate in Jacksonville, where he’s pitched well.
In 43 2/3 innings with the Jumbo Shrimp, Martinez has a 3.71 earned run average. He’s fanned a strong 28.9% of his opponents against a 9.6% walk rate that’s just barely north of the 9.3% MLB average for relievers. He’s sitting 89-90 mph with both his four-seamer and sinker, but Hernandez is using his slider more than at any point in his career; his 46.7% usage rate actually makes the slider his primary offering. It’s worked well thus far, evidenced not only by the previously mentioned rate stats but also a sharp 13.1% swinging-strike rate and poor batted-ball metrics from his opponents (87.5 mph average exit velocity, 33.9% hard-hit rate).
This could prove to be little more than a cup of coffee for Martinez, but he’s pitched well enough in Triple-A and has enough track record that it wouldn’t be too surprising if he pitched his way into some staying power. Martinez is out of minor league options, so he can’t simply be sent back to Triple-A. He’d need to pass through waivers, and his prior outright assignment means he’d have the right to elect free agency even in that scenario. If he does stick around on Miami’s roster, he can be controlled for four additional seasons.
As for Junk, it’s an ill-timed injury for a journeyman righty who’d created some staying power of his own. Miami is Junk’s sixth organization since 2021, and he came to the Fish with a 6.75 ERA in 40 career big league innings. He’s unlocked something in South Florida, however, tossing 88 innings with a 4.09 ERA. Janson’s 17.2% strikeout rate could charitably be described as pedestrian, but he’s shown some of the best command in the majors this year, issuing a walk to only 2.8% of his opponents. The 29-year-old had solidified himself in the Marlins’ rotation with that performance.
Time will tell whether Junk makes it back to the mound this year, but with only a month left on the regular season calendar, even minor injuries can prove to be season enders. If his season is finished, it’ll easily be the most successful of his career. Miami can control Junk for another five seasons if they choose, and he won’t be eligible for arbitration until the 2027-28 offseason.