SEATTLE -- The piggyback will get another go, but it’s on the way out.
The Mariners will go back to the piggyback in the fifth spot in the rotation one more time, with Bryce Miller slated to start Sunday’s finale against the D-backs and Luis Castillo in line to come out of the bullpen.
But sources familiar to the club’s thinking told MLB.com’s Daniel Kramer that after that, Seattle will shift to a six-man rotation, lining up both Castillo and Miller to start.
There’s no public timeline as to how long the six-man rotation will last. The move comes with the club opening a stretch of 16 games in 17 days with the beginning of their homestand Friday, and the Mariners open June with 18 games in 20 days.
Seattle’s first two run-throughs with the paired-up system featured a wild disparity between results and overall reactions from all parties involved.
On one hand, Miller and Castillo have combined to allow four runs in 17 innings with 21 strikeouts in their two piggybacks, including last Monday when they covered all nine innings in a comfortable win vs. the A’s.
On the other hand, both piggyback days ended with both pitchers visibly upset … including last Monday, when the Mariners’ win was overshadowed by scenes of Castillo slamming his glove in the dugout after Dan Wilson told him he was done after just four innings, and Miller said he had only found out he’d be the one coming out of the bullpen two days prior.
“As a competitor, you kind of want to go out there and just continue,” Castillo said through an interpreter after that game. “But at the same time, you've got to respect his position. We knew that was part of the plan, and you've got to respect what his decision was.”
It’s been a tricky situation for the club, ever since Miller returned from the right oblique injury that put him on the injured list to begin the year. In his two appearances, the 27-year-old has posted a 2.25 ERA with 14 strikeouts and two walks across 16 innings. Castillo has had a more up-and-down start to the year, but showed his best stuff against the A’s -- and is also the Mariners’ most experienced and highest-earning pitcher.
Meanwhile, Emerson Hancock, who began the season in Miller’s place in the rotation, has turned into arguably Seattle’s most consistent starter, with a 2.78 ERA and a 1.01 WHIP in 11 starts, making it impossible to move him back to the bullpen as the club did last season.
After those scenes in Sacramento, president of baseball operations Jerry Dipoto, Wilson and pitching coach Pete Woodworth all met with Miller and Castillo to address the breakdowns in communication and the plans moving forward.
By the looks of it, those plans involve both Castillo and Miller starting -- and soon.