"The Cubs desperately want another starter at the deadline, targeting Mitch Keller of the Pirates, and would include outfield prospect Owen Caissie to make it work," Nightengale wrote on Sunday. Keller has previously been an All Star, and he would be a boost near the front of the Cubs' rotation.

Left-handed starting pitcher Kris Bubic has a limited track record of success, but he's been elite in 2025. Bubic has a 2.38 ERA, ranking sixth in MLB and fourth in the American League among starting pitchers. Out of his 19 starts in 2025, Bubic has only allowed more than three earned runs twice.