State of the Mariners’ rotation — where Justus Sheffield, Yusei Kikuchi and more stand going into 2021

In a Mariners season dedicated to getting young players experience and finding out what they were at the big league level, every game is precious.

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For the hitters, 200-250 plate appearances in 60 games gives a partial view. A lot was learned in the case of the Mariners, but there are questions about what was real – both on the positive and negative sides – in a smaller sample for young players.

For the pitchers, the story is a little different. Their stuff is easier to evaluate. A big league pitch is a big league pitch no matter who it is thrown to or what field it is thrown on. If the stuff plays, the numbers will tell you. Instead, the questions come in different areas.

Preparation, execution of pitches, game management – in simpler terms, can the player put it all together and do what it takes to keep it together at the highest level. A 10-start sample gives a good picture, and in 2020 the Mariners were able to learn enough about the three young pitchers in their rotation as well as Yusei Kikuchi, who made big changes coming off a very rocky rookie campaign, to help solidify plans for what happens next.

Yusei Kikuchi

Marco Gonzales, who opened eyes building on a solid foundation that earned him a four-year extension in the offseason, is obviously locked in for 2021, as is Kikuchi, who is signed through 2021 and holds a player option for 2022. While the 5.17 ERA Kikuchi posted in nine starts is ugly, other numbers paint a different picture. His FIP, 3.30, is over two runs lower than his 2019 ERA. Hits per nine innings went down from 10.9 to 7.9,  home runs per nine from 2.0 to 0.6, and strikeouts per nine up 6.5 to 9.0.

This represents dramatic change, coming after an offseason dedicated to making changes, which is encouraging moving forward. Kikuchi has upped the velocity on all of his pitches, most notably the fastball which averaged 92.5 mph in ’19 and sat at 95 in ’20, and added a cutter that proved effective against right-handers. He has developed a nice arsenal that helped lead to much improved hard-contact numbers, and now the challenge is putting it all together.

His walks per nine jumped from 2.8 to 3.8 and there were games he could not find a way to get out of trouble. A good chunk of his 5.17 ERA comes from those outings when he handed off the game to relievers with runners on base.

Kikuchi himself is aware of what stands between him and putting up the numbers that should come with the changes he made with his pitches following the ’19 season. To that end, he told the Japanese media at the end of the year that his focus this offseason would be more on the mental side of the game. The Mariners have sent him home with an offseason plan to assist with this and in other areas.

Justus Sheffield

The picture perhaps is a little clearer for Justus Sheffield, who came through his “show me” season with flying colors, posting a 3.58 ERA and 3.17 FIP, and allowing just seven extra-base hits in 10 starts.

Sheffield was good on paper but even better in person. We learned in spring training that he was not afraid to make major changes, taking a two-seamer he had learned between starts into a game and committing to it, not throwing a single four-seamer that outing. Ditching your bread and butter pitch is not an easy thing to do and for Sheffield, the change went well beyond the grip.

“When I was throwing my four-seam I always thought I was a power pitcher,” he pointed out. “I was going to blow doors and ‘here it is.’ Up here I’ve noticed these guys can hit 97, 100 mph like it’s 90 mph. If I want to be a starting pitcher, I’m going to need to learn how to change speeds, work the inside and outside of the plate. More, ‘Hey man, there’s a spot.’ Drive it to your locations, mix your pitches, change speeds and keep hitters off-balance.”

In other words, be a pitcher.

It’s a dramatic change to make in-season and there is still work to be done, particularly in improving his third pitch, the changeup. But another factor that no doubt helped has been the guy at the top of the rotation setting the example.

“Marco, he’s legit,” said Sheffield. “The work that he puts in on the field, off the field, his intellect of pitching, being able to get guys out and pitch guys, it’s incredible honestly. It’s something that I want to strive to be able to do because it’s special. The way he games plans and knows the game, how to pitch to guys, you can tell he does his work and he continues to get better game by game and year by year.”

Justin Dunn

The Mariners leaned on Gonzales to help lead the young starters going so far as to letting Justin Dunn sit in on one of his game planning sessions. That session, like most of his first “full” season in the big leagues was eye opening for Dunn, whose performance in 2020 left many questions unanswered.

Of concern, his velocity was down from what it was in the minors. Mariners manager Scott Servais has pointed to the shutdown as likely being the problem here, but a bigger concern was Dunn’s lack of command. In Double-A he posted a 39/158 walks to strikeouts rate in 2019. In 2020 that rate was 31/38. The ERA was a palatable 4.34 but the FIP 6.54, almost a reverse Kikuchi. Where Kikuchi wasn’t able to find his way out of trouble, Dunn walked his way out of it.

In some cases Dunn was able to find it after the problematic inning and go on to pitch a good game. In others, Servais had to go to the pen. One of those games, a start in Arizona where he walked five in 2 innings, came the day before a doubleheader where bullpen would be needed. After the game, Servais’ comments were concerning.

“You always have to come mentally prepared,” Servais said. “He missed some signs early, he had a hard time connecting with the catcher. He just wasn’t there today. He’ll learn from it. That’s part of the process with young players.”

It’s worth noting here that Dunn is just 52 innings into his big league career and surprises do arise early. In that start, Dunn admitted that he perhaps had let up on the gas a bit with his focus coming off three successful outings.

“I kind of thought I had some things figured out. I won’t say hit the cruise control but the mental focus wasn’t there as much,” Dunn said later that week. “What really got me was the inability to snap back to where I needed to be. Things were spiraling. I knew there were going to be days over 162, that’s not going to be the last time that happens. It was a learning moment for me in having to make sure that I am mentally locked in as much as I can be for every single one of my starts.”

Dunn bounced back nicely in his next start, holding the Padres hitless for five innings. Still, he walked four batters in that outing, not commanding the game the way he ideally would like to. At best he survived at the big league level in 2020, but Dunn believes he saw enough from his stuff to expect more in 2021.

“It plays when I get it over the plate,” he said. “Get strike one, get strike two. If I can get guys in swing mode, my stuff will play, but I let them get too passive this year.”

A lot to unpack after his first season in the big leagues but lessons learned now could prove valuable moving forward.

Nick Margevicius

Nick Margevicius got a lot of firsts out of the way in 2019 as a 23 year old who was promoted from High-A to the bigs out of spring training when the Padres had a need in their rotation. With the Padres’ farm system loaded with talent, he became a victim of roster crunch, and the Mariners were able to claim him off waivers in February to give them starter depth and an interesting option all wrapped up in one pitcher.

At first glance, Margevicius would seem to fall into that kind of sixth or seventh guy at the ready in the minors as the numbers across the board are far from spectacular. Off the paper and in front of you, however, things get a little more interesting when you remember that he is a young pitcher who came from a small college and is still progressing.

Then there are the intangibles.

“I feel like he is a 34 year old trapped in a 24-year-old body,” said Mariners pitching coach Pete Woodworth. “Very intelligent, very cerebral, very aware of everything he does. Marco is the best I have been around in of knowing routine and what he needs to do on any day, just a professional in every avenue. Marg is just right behind him. There’s always a plan, there’s always a process, there’s always focus. He does everything the right way. I don’t want to say he surprised us because we knew we were getting a really good piece, but he just continues to develop in every aspect. The stuff is getting better, the command is getting better, the body is getting better. That’s just who he is.”

How far he gets in that development will determine how long he lasts in the Mariners rotation. In his preparation for the 2020 season, Margevicius made a trip to Driveline Baseball in Kent to get an evaluation and offseason plan. A weighted ball program helped raise his fastball velocity from 88 mph to 90. He also went to work on pitch shaping and saw improvement in that area as well. When he arrived to the Mariners he was excited to hear that the analytics and pitching performance staff had a lot of the same ideas of what he had already set out to do.

A favorite question of mine since his acquisition has been, “Just what exactly is a Margevicius?” We are still finding out. In his final start of the season, Margevicius threw six innings of shutout baseball against the Houston Astros. It was a day where he didn’t have a good fastball and he leaned instead on a newer pitch, a low velocity curveball.

After the game, Servais had high praise for what they had seen from Margevicius since taking over for Kendall Graveman in the rotation.

“He landed in the right place,” Servais said. “I love having him out there. I love how he competes and he’s only going to get better. It’s left-handed, you throw strikes, you are coming up with some other pitches and really have got some guts and heart to you. You are going to win a lot of games in this league and I truly believe he is.”

The Mariners could comfortably fill five of the six spots in the rotation with the starters profiled above, but unlike 2020, at some point in 2021 competition for spots should arise. It could be at the start with Mariners general manager Jerry Dipoto planning on bringing in at least one starter in the offseason (with Taijuan Walker being a preference), and perhaps a depth or risk/reward type player also acquired. There’s also the possibility that the market could prompt another addition if Dipoto sees value that he can’t pass up.

Then there is the matter of 2018 Mariners first-round pick Logan Gilbert, who should arrive in the majors at some point in 2021. This won’t be as clear-cut as it would have been in 2020 as Gilbert’s innings will have to be carefully managed coming off a season where he threw in exactly zero games, but one way or another he should debut in 2021.

If tough decisions need to be made at that time, then 2020 will have proved to have been a very big success when it comes to starting pitching.

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