The trade: The Mariners acquire RHP Luis Castillo from the Reds for SS Noelvi Marte, SS Edwin Arroyo, RHP Levi Stoudt and RHP Andrew Moore.
With the Mariners in a wild-card position and looking to end an epic playoff drought that dates back to the stone ages (at least in sports years) of 2001, you knew general manager Jerry Dipoto was going to make a move -- and maybe a big one. He didn't disappoint. The Mariners were believed to be one of the leading contenders to acquire Juan Soto, but Dipoto instead snapped up Castillo, viewed as the top starting pitcher available (barring a shocking Shohei Ohtani trade), and outbidding teams like the Yankees, Dodgers and Cardinals who were also in hot pursuit of Castillo.
Let's go to the grades.
The Mariners are 17-5 over the past 22 games to put themselves in playoff position, but all five of those losses have come against the Astros since the All-Star break, with the Mariners scoring just 11 runs in those defeats. So that's why they were in on Soto; they do need to improve an offense that is 11th in the American League in runs per game. But they faced another issue: Rookie George Kirby is nearing an innings limit, with 94 innings on the season after pitching just 67.2 in 2021 in his first full season as a professional. Without a viable No. 5 starter, they did need another starter to eventually replace Kirby in the rotation.