Mariners hope another starter can make a leap like Justus Sheffield did

Among many positive signs for the Seattle Mariners during the shortened 2020 season was the showing young starter Justus Sheffield made in his first full season in the big leagues.

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Sheffield had trouble finding his footing in 11 MLB appearances combined between 2018 and 2019, making last season very much a prove-it year for a once highly-touted prospect who was the key to the Mariners’ return in the trade that sent James Paxton to the Yankees after the 2018 season.

The 24-year-old left-hander very much did some proving in 2020, posting a quality start in six of his 10 outings and allowing two runs or less in seven of his last eight games, six of which saw him make it through at least six innings. It curiously didn’t get the 24-year-old southpaw any votes in the Rookie of the Year race, but Sheffield’s season turned heads and provided a lot more confidence in his future with the Mariners.

In 2021, the M’s hope another of their young rotation members follows in Sheffield’s footsteps.

Justin Dunn, who was part of Seattle’s big trade in the offseason prior to 2019 that sent Robinson Canó and Edwin Díaz to the Mets, had a 4.34 ERA, 1.358 WHIP, and 31 walks to 38 strikeouts in 10 starts last season. Command was certainly an issue, though he showed some promise with four outings where he made it through six innings and allowed two runs or less.

On Tuesday night, Mariners assistant general manager and vice president of baseball operations Justin Hollander joined The Hot Stove Report on 710 ESPN Seattle and shared how he thinks the 25-year-old Dunn has a chance to do something similar in 2021 to what Sheffield did last year.

“I think Justin is kind of in the place where Justus was two years ago,” Hollander said. “Justus had the struggles in ’19 and really took his game to the next level. He saw what the big leagues were about, he made some changes and then went and attacked the league and showed them that ‘I’m good enough.’ Justin navigated really well last year. He showed that he’s a competitor and that he wants to compete – even without his best stuff, even without his best command – and I think you’ll see a much better, more equipped version of Justin Dunn to go out and compete in the big leagues this year.”

Dunn had just four appearances and 6 2/3 innings of work in the big leagues before 2020, and in the case of Sheffield, he clearly took a step forward the year after his first extended look at the MLB level, which is what 2021 will be for Dunn.

“I couldn’t have been happier for Justus,” Hollander said about Sheffield’s 2020 season. “Coming off of the struggles that he had in the previous season, I think he felt the burden of ‘I’m replacing James Paxton’ in a lot of ways in ’19. For him to come out and do what he did and add the two-seamer and really just the confidence, the swagger, (to see) he’s an over-the-top competitor, just watch what he did and how he grew last year, it was awesome.”

Hollander was just the first of many guests during the two hours of the latest edition of The Hot Stove. Also joining hosts Rick Rizzs and Gary Hill on the show were Mariners utility player Dylan Moore, Mariners director of international scouting Frankie Thon Jr., Houston Astros broadcaster Steve Sparks, and our very own Mariners insider at 710 ESPN Seattle, Shannon Drayer. You can listen to Hollander in Hour 1 of the show at this link or in the player below. Hour 2 of the show can be heard at this link.

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