Cubs add Carlos Santana after Guardians released him, aiming to boost first-base and lefty-matchup depth as September nears. Santana, a switch-hitter, could spell Michael Busch against left-handers while Suzuki and Turner shoulder the middle-of-the-order load. Cubs also sign Aaron Civale off waivers, giving a rotation depth boost as Taillon and Soroka deal with injuries. With Porter Hodge and others in play, Chicago eyes a stronger stretch-drive and a postseason-ready roster by Sept. 1.