Megill was recalled from Triple-A Iowa on Thursday, Gordon Wittenmyer of NBC Sports Chicago reports.
Megill was sent to the minors in late June, and he allowed two runs on three hits and a walk while striking out 11 in six innings during his stint with the Triple-A club. He'll provide a fresh arm out of the bullpen for the Cubs, while infielder Sergio Alcantara was sent down in a corresponding move.