Clooney and Wyle, who played Doug Ross and John Carter, respectively, starred alongside each other on the hit medical drama for five seasons before Clooney exited the series to focus on other acting endeavors. Wyle continued with the show through season 11, making guest appearances in seasons 12 and 15. ER ran from 1994 to 2009.

Like everyone else, George Clooney is watching "The Pitt," the acclaimed medical drama series starring his former "ER" colleague Noah Wyle.

"He never had trouble, he always could do it," Clooney said, quipping, "I hated him for that." Meyers joked, "I think we all should. I think it's unfair." Clooney then deadpanned,