Mariners planning to return to 6-man rotation in 2021, some spots open for competition
The Mariners are planning to stick with what worked for their young starting pitchers in the shortened 2020 season.
That means a return to the six-man rotation in 2021.
Mariners manager Scott Servais said in December he thought the retooled rotation “worked great last year.”
“I think it’s really a benefit for our younger pitchers,” he said. “Having that extra day allows them to work on some things a little bit more aggressively between starts. … I think it helps a lot of different guys, because we’re seeing better stuff when they go out there the sixth day.
“Also, it allows me to give them a little bit longer leash, let them try to work through some of the traffic and the situations that come up.”
General manager Jerry Dipoto doubled down on those ideas Tuesday during a media call as part of the club’s Virtual Baseball Bash.
“On multiple levels, the six-man rotation in 2020 we thought was a better way to preserve health and really further development,” he said.
Continued development and keeping innings at a manageable volume is what the Mariners are focused on heading into the spring.
“The six man rotation allows for two bullpen days,” Dipoto said. “It allows for two work days in between, and when your starting pitchers are all generally aged 24-26 and have less than a year’s experience, those work days are really important.
“It allows for pitch development and pitch shaping. It allows for training on delivery refinement and command. It’s not just about getting out every fifth day and performing. It’s very much still development program.
“We feel like that’s a huge advantage with the six-man with such a young staff, and it is still a young staff, and that’s an important element here.”
So is keeping the club’s young arms healthy. Even in what is expected to be a full 162-game slate in 2021, the extra rest day gives starters the chance to steadily build up their workload again.
Only 17 pitchers tossed more than 70 innings in 2020 — Texas’ Lance Lynn topped the majors at 84 — which is less than half of the roughly 160-200 innings starters can reach in a normal year.
Mariners ace Marco Gonzales led the club in innings last season with 69 2/3 across his team-high 11 starts.
“The highest volume starters in 2020 were guys that threw 60-80 innings, and that’s not a high volume of innings in the grand scheme of things,” Dipoto said. “We feel like the jump from 60-80 to say 140-150 is reasonable for the guys who might have been at the top end of that scale, to get them into a 160-170 type of range is reasonable. Going beyond that is not likely, and we feel like this allows us to help govern that.”
So what might a Mariners six-man rotation look like in 2021?
Gonzales, entering his seventh year in the majors and one of Seattle’s more veteran players at 28 years old, is expected to resume his role atop the rotation after finishing the shortened 2020 season at 7-2 with a career-best 3.10 ERA.
Yusei Kikuchi, who finished his second season in the majors at 2-4 with a 5.17 ERA, but displayed a more refined approach and an uptick in velocity, is also slotted to return.
So is Justus Sheffield, the 24-year-old who wrapped up an impressive rookie campaign in 2020 with a 4-3 record and 3.58 ERA to solidify his spot moving forward.
The three lefties are locks for the rotation, and Dipoto said recently signed right-hander Chris Flexen will also be part of Seattle’s six-man rotation.
Flexen agreed to a two-year deal with the Mariners in December after pitching last season for the Doosan Bears of the Korean Baseball Organization and posting an 8-4 record and 3.01 ERA in 21 starts with 132 strikeouts to 30 walks.
He pitched eight seasons in the Mets system prior to that, made his big league debut in 2017 and appeared in parts of three seasons for New York from 2017-19 as both a starter and reliever.
Dipoto said in a release following the announcement that Flexen is “a natural fit as we continue to grow our young core.”
The remaining spots in Seattle’s rotation? Those are still up for grabs.
“That allows for two open spots that are generally going to be competitions,” Dipoto said. “It’s going to be some combination of Justin Dunn and Nick Margevicius and Logan Gilbert, and perhaps others who aren’t necessarily currently in the Mariners system, and it could extend to players like an Ljay Newsome or minor league free agents that will be given further opportunity.
“But, we feel like there’s still something to go add in that space. We won’t go in short.”
Gilbert, who is considered Seattle’s No. 3 prospect by Baseball America and No. 4 prospect by MLB Pipeline, is also expected to make his big league debut at some point this season.
Dipoto said he believes Gilbert is the “closest to major league preparedness” of the club’s prospects.
“Where he is emotionally, what he does physically, he was outstanding at the (alternate) site during the summer last year,” Dipoto said.
Dunn, Margevicius and Newsome all took turns in Seattle’s rotation during the shortened season.
Dunn opened 2020 in the rotation, and finished 4-1 with a 4.34 ERA across 10 starts.
Margevicius eventually replaced injured starter Kendall Graveman — who is now in the Mariners’ bullpen — early on, and finished 2-3 with a 4.57 ERA in 10 appearances (seven starts).
Newsome took Taijuan Walker’s spot after Walker was traded to the Blue Jays at the August deadline and posted a 5.17 ERA across five appearances (four starts).
“We feel confident in the group that we have today and we were very excited by some of the development with guys like Marge and like Ljay Newsome, and what we saw, though it was sometimes turbulent, (with) the fact that Justin Dunn got through his first season and learned a lot,” Dipoto said.
“We are all going to be better for the experiences that these guys had in 2020, but we won’t overload them with innings, and we do want to make sure that we still have those work days in between, because it is largely a young group.”
