Let's go back to the 2022 trade deadline. Hot in pursuit of their first playoff berth in decades, the Seattle Mariners acquired Luis Castillo from the Cincinnati Reds. He had been a key piece of Cincinnati's rotation since being called up in 2017, and was poised to lead what was at the time an underwhelming starting pitching unit in Seattle.
Because of his established reputation and the Mariners' need, he didn't come cheap. Seattle conceded four prospects, three of which were in the organization's top 10. Nonetheless, Castillo fulfilled his role and helped lead his new team to the playoffs.