Veteran Infielder Leo Rivas, Left-Handed Pitcher Jhonathan Diaz Optioned to Triple-A

The re-addition of Diaz to the Rainiers' pitching staff will be needed. According to a report from MLB.com's Daniel Kramer, Seattle plans on calling up starter Luis F. Castillo for his first-ever major league start for Friday's series opener against the San Francisco Giants.

Diaz made one appearance for the Mariners and pitched 1.1 innings. He struck out one batter and allowed one hit. Before he was called up to Seattle, he was scheduled to make his first start of the season in Triple-A.

Rivas didn't see the field for the Mariners in his two games up. He played three games for the Rainiers before having his contract selected. He was hitting .200 (2-for-10) with two homers, two runs and four RBIs.

"(That home run) felt amazing," Rivas said in an interview Wednesday. "Feels amazing. First hit of the season, a homer like that, I'm like 'Oh now (we're going).'"

Rivas already has half as many home runs in his first three games with Triple-A this season as he did all of 2024. He hit .296 with four homers, 32 RBIs and 24 steals in 63 games last season. Both players will likely continue to be up-and-down between Tacoma and Seattle as the season progresses. Either could have an extended stay on the major league roster based on injuries or other external factors.

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