Mariners Trade Castillo to Orioles for Cash in Roster Move

SEATTLE, Wash. — The Seattle Mariners announced on Thursday that they have traded right-handed pitcher Luis Castillo to the Baltimore Orioles for cash considerations. Castillo was designated for assignment by Seattle one day earlier as part of a corresponding move following a waiver claim.

In response, Baltimore optioned Castillo to their Triple-A Norfolk affiliate and designated left-handed pitcher Austin Pennington for assignment to create space on their 40-man roster.

Castillo has made five appearances in Major League Baseball and had signed a minor league deal with Seattle during the offseason. He was called up to the big league roster in early April, where he made two starts, allowing seven runs (six earned) on 12 hits and seven walks across seven innings while striking out five batters.

His previous experience in the major leagues consisted of three relief outings for the Detroit Tigers in 2022, after spending the last two seasons in Japan. While in Japan, Castillo had a lower 2.96 ERA over 94 1/3 innings with the Orix Buffaloes last year, although he struggled to make batters miss.

At 30 years old, Castillo has now made four starts for Seattle’s Triple-A team in Tacoma, achieving a 12:5 strikeout-to-walk ratio while giving up eight runs in 14 1/3 innings pitched.

Castillo throws a four-seam fastball and sinker that both sit in the 91-92 MPH range. His ability to induce swings and misses is limited, but he possesses minor league options which will assist him in continuing to develop.

Pennington, 27, finds himself in a similar situation as he is placed back into DFA limbo for the second time in just a few weeks. After being released by the Texas Rangers in late April, he was picked up on waivers by Baltimore, where he made two appearances — one at High-A Aberdeen and one with Norfolk. However, his performance has been troubling, as he walked six of the 10 batters faced and allowed seven runs (five earned) in a single inning.

Originally drafted by the Kansas City Royals, Pennington was traded to Texas last summer during the trade deadline. He had previously shown promise with a 2.13 ERA and a 32.2% strikeout rate over 63 1/3 innings in Triple-A.

If the Orioles do not find a taker for Pennington on waivers in the coming days, he may be outright assigned, as he currently lacks the service time to decline such an assignment.