"Late Show" host Stephen Colbert had some fun at the expense of former Vice President Joe Biden and mocked him for his age during a live post-debate broadcast.

In his opening monologue, the left-wing funnyman offered reactions to several highlights of Thursday night's Democratic debate. He took aim at the 2020 frontrunner when Biden said: "I refuse to postpone one more minute."

"'Because I clearly don't have a lot of time left,'" Colbert said impersonating the candidate.

The joke drew some mixed reaction, but the CBS star attempted to smooth over the one-liner by blowing Biden a kiss to the camera.

BIDEN MOCKED FOR ENCOURAGING KIDS TO LISTEN TO 'THE RECORD PLAYER' AT DEBATE

This comes after former Housing and Urban Development Secretary Julián Castro attacked Biden’s memory, accusing him of contradicting himself about whether Americans would have to buy into a public health care option under his plan or if they would be automatically enrolled.

“I can’t believe that you said two minutes ago that they had to buy in, and now you’re saying they don’t have to buy in,” Castro said. “You’re forgetting that!”

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Sen. Cory Booker, D-N.J., expressed solidarity with Castro following the debate, saying that there are moments when Biden speaks that make you "wonder."

"I think we are at a tough point right now, because there’s a lot of people concerned about Joe Biden’s ability to carry the ball all the way across the end line without fumbling," Booker began when asked about Castro's remarks. "And I think that Castro had really legitimate concerns about can he be someone in a long grueling campaign… and has every right to call out.”