The Mariners have acquired right-handed starter Mike Leake from the Cardinals in exchange for minor-league infielder Rayder Ascanio. The Mariners will also receive cash and international slot money in the deal. 

Leake, 29, has pitched to a 4.21 ERA (101 ERA+) and 2.94 K/BB ratio in 154 innings this season. For his career, he owns an ERA+ of 99 across parts of eight big-league seasons. This season, his numbers have declined significantly in the second half, so the M's will of course be hoping he can arrest that decline. Prior to the 2016 season, Leake signed a five-year, $80 million contract with St. Louis, and he's still got roughly $55 million remaining on that deal. 

Seattle remains in the mix for an AL wild card berth, but the rotation has been waylaid by injury. At present, five Mariner starting pitchers are on the disabled list, including Felix Hernandez, James Paxton, Drew Smyly, and Hisashi Iwakuma. In related matters, the Mariners have given one or more starts to 16 different pitchers in 2017. The Leake acquisition directly addresses the hole in the rotation as the M's head toward the stretch drive. 

On the Cardinals' side of things, Ascanio, 21, has batted .240/.320/.329 across parts of five minor-league seasons. while seeing time at short, second, and third. The likely motivation is salary relief. As Nightengale suggests, this may signal preparations to engage pending free agent starter Lance Lynn leading up to the offseason. As fas the near-term is concerned, the Cardinals will need to add a fifth starter to a rotation that presently includes Carlos Martinez, Lynn, Michael Wacha, and Luke Weaver. Veteran Adam Wainwright is currently on the DL with an elbow impingement.