The transaction itself was simple enough. The Astros claimed Rhylan Thomas off waivers from the Mariners after Seattle designated him for assignment to make room for left-hander José Suarez, whom the Mariners had claimed from the Braves. Houston then created its own roster space by shifting Hunter Brown from the 15-day injured list to the 60-day IL. The mechanics are ordinary. The destination is what makes it annoying. Thomas is not a can’t-miss prospect the Mariners simply let slip away. Seattle originally acquired him from the Mets in the 2024 Ryne Stanek trade, and he only received a brief major-league look with the Mariners last season. He had one hit and one walk in 10 plate appearances before returning to Triple-A Tacoma. His strongest case came in 2025, when he hit .325/.380/.411 over 617 plate appearances for the Rainiers. But that production had cooled this season, with Thomas down to .260/.313/.328 through 145 plate appearances.…