Drayer: Why the Mariners won’t be changing to a 5-man starting rotation

In the absence of Marco Gonzales, who is on the Mariners’ 10-day injured list with a left forearm strain, the Mariners will go with a bullpen day in lieu of a regular starting pitcher in their Monday night series opener against Baltimore.

Mariners set minors rosters: Kelenic in Tacoma, Rodríguez in Everett

This decision has prompted the question from some of “Why?” when it would appear there are other options. Many would like to see the Mariners go back from their six-man rotation to a five-man, but manager Scott Servais said Sunday that is not in the cards.

“Not at this point. I think if you are looking at our schedule over the next 10 days, we have a couple of off days in there which will benefit our bullpen guys quite a bit,” he said, noting that Keynan Middleton and Robert Dugger had recently had outings of multiple innings.

“You are going to need guys like that to step up. But as far as the rotation goes with those off days coming up – and I’m very hopeful that Marco Gonzales is not out that long, maybe just a couple of starts missing him but we will have to wait and see how that comes along – but as of right now, no, we are not looking at going to a five-man rotation.”

While they have burned through their starter depth, the Mariners did have depth to draw from in their reliever pool. Knowing that they would have to lean on their relievers, the Mariners added another arm to the pen this weekend in a roundabout way with Domingo Tapia taking Gonzales’ spot on the roster, Wyatt Mills called up to replace catcher Jacob Nottingham (who was designated for assignment Saturday and traded back to Milwaukee Sunday), and Erik Swanson taking the place of Casey Sadler, who was placed on the 10-day IL with right shoulder inflammation Sunday.

The bullpen that started the season with eight relievers now has at least has nine for the short term, which leaves just two position players on the bench.

Mariners bullpen

• Rafael Montero
• Kendall Graveman
• Keynan Middleton
• Anthony Misiewicz
• Will Vest
• Drew Stecknerider
• Robert Dugger
• Domingo Tapia
• Erik Swanson

How long the Mariners stick with a nine-man pen remains to be seen, with a move needing to be made when first baseman Evan White returns from the bereavement list. But for now, they have extra help.

As for the reasons why not to go back to a five-man rotation? If you talk to general manager Jerry Dipoto, he points to arm health first, the extra work day the starters receive second. In Servais’ eyes, the extra work day is very valuable to the young pitchers in particular. Arm health coming off 2020’s start/stop and then quick buildup to a two-month season is what originally sparked the idea to run with a six-man rotation for a second straight year.

There are other reasons why a six-man rotation might be a better fit for the Mariners than other teams, however.

For one, the youth. Justin Dunn, Justus Sheffield and Chris Flexen have never pitched a full major league season. Three of the starters have spent considerable time before this year pitching on a six-man schedule, as well, with Flexen doing so for the majority of the season last year in Korea’s KBO, Yusei Kikuchi being brought up in Japan’s NPB where starters get five days of rest, and Dunn doing the same at Double-A in 2019 as the Mariners utilize the six-man rotation throughout the minors.

At some point it’s hard to see the Mariners not going back to a five-man rotation. In large part, starters are paid to pitch every five days. There’s value in that and the better starters you have, the more you want them pitch. For fans who don’t understand why the Mariners would roll the dice on a bullpen start or lesser arm every sixth day when it could seemingly just as easily flip back to the No. 1 or No. 2 arm and a better chance at a win, it’s important to remember where they are and what their priorities. The fact of the matter is they are still in a development phase, and with young starters and the uncertainty of build up – particularly for young starters who haven’t pitched a full MLB workload as of yet – the decision was to prioritize them (and Logan Gilbert when he arrives) with much thought and research put into the decision.

It’s a decision that former big league starter/reliever Ryan Rowland-Smith understands.

“I think it would be a big one,” he answered when asked on a recent Mariners postgame show on 710 ESPN Seattle how much of an adjustment switching would be. “Even from the beginning of spring training, here’s your routine, here’s your day off, and then boom, the end of April, OK, now we are going to have to switch that around? These routines, they are really structured especially for these young pitchers, Justin Dunn in particular. I think if they can somehow keep the priority Sheffield, Kikuchi, Dunn, keep the routine the way it is, you also have the factor in that they only played 60 games last year. It’s an interesting situation. I just think the priority now is find another arm and stay in that six-man rotation.”

Finding another arm is easier said then done. Within the organization, the only starter remaining on the 40-man roster is Juan Then, who is slated to start his season at High-A Everett. Jimmy Yacabonis pitched starter innings at the Mariners’ alternate site last year and could be an option with a spot on the 40-man roster available when needed as Sam Delaplane has yet to be put on the 60-day IL. Dipoto has no doubt been scouring the waiver wire and on the phone searching for a short-term fix. Is it too early to find a Wade LeBlanc or Tommy Milone-type stopgap? Probably, but the off days in early May should give Diptoto some time.

Running with a depth arm in the rotation who has to date shown to be better suited for long relief in the fifth spot (Ljay Newsome) and “Johnny Allstaff” in the sixth is clearly sub-optimal for the Mariners. Regardless of when Gonzales returns – and there were promising signs Sunday with Gonzales throwing on the field with a trainer before the game – more arms will be needed as it didn’t take long to prove that what the Mariners had was not enough.

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