Orioles execute late-night trade with Mariners for journeyman reliever

The Baltimore Orioles need an enormous amount of help on the pitching side. Changes have to be made in a bullpen that ranks 27th in baseball in ERA. Opponents have a .288 batting average against Orioles pitching. The league average for team batting average is .243 this season.

It's not an out-of-nowhere move for an All-Star, but Baltimore's trade Wednesday night was something. The Orioles announced they acquired right-handed reliever Luis F. Castillo from the Seattle Mariners in exchange for cash considerations. Castillo had been designated for assignment by Seattle.

No, it's not the three-time All-Star and former Cincinnati Reds pitcher Luis Castillo. It's a 30-year-old who made his professional debut in 2012. He's spent most of his time in the minors, but Castillo has made five MLB appearances, two this season.

He can be described more as a swing pitcher. Both of Castillo's appearances with the Mariners this year were starts. He allowed six earned runs across seven innings for a 7.71 ERA, walking seven batters with five strikeouts.

What is Baltimore's plan with Luis F. Castillo?

The Orioles optioned Castillo to Triple-A after the trade. Whether he'll pitch as a starter or reliever has not yet been announced. Nearly 85% of Castillo's minor league appearances came as a reliever, so Baltimore might try to keep him stretched out as a long reliever.

If there's a world where Castillo is starting games for the Orioles, that's not a great world for Baltimore to be in. It would mean the O's have a few injuries in their rotation, or that the starters are still putting up brutal numbers.

There's a chance Castillo gets a shot in Baltimore's bullpen. He has a career 3.53 ERA in the minors and did not allow a run in three relief appearances in 2022, including his debut. Castillo isn't a huge strikeout pitcher, but he does have a respectable 3.17 career strikeout-to-walk ratio in the minors.

The Dominican righty was added to the 40-man roster, with Walter Pennington getting DFA'd. The O's claimed Pennington off waivers from the Texas Rangers in late April.

Orioles getting key piece back

The Orioles' pitching staff received a jolt before Wednesday's game, in the form of Zach Eflin. Manager Brandon Hyde announced Eflin will return from a lat injury and start a game against the Los Angeles Angels this weekend. Eflin missed a month and needed only one rehab assignment to get right.

It's good news for Baltimore. Perhaps the O's can get some stability from their starting rotation. They have nine quality starts in 35 games. Eflin is responsible for three of them. All but two of his 12 starts since being traded to the Orioles were quality starts, and he's never allowed more than three runs. He'll be relied upon to bring those same numbers again.

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