The Black Keys competed to examine Stephen Colbert's rectum last night...

Last week Today show hosts Al Roker and Matt Lauer were given an on-air prostate exam. It was pretty awkward. But to follow it up the way only Stephen Colbert can, the Colbert Report host decided he would take the exam up a notch.

"Nation, any news man can get some old doctor to still his digital up your analog. But Sweeps is all about guest stars."

And in walks John Lithgow. "Stephen, I'm here to examine your prostate as research for an acting role [for the play] The Glass Menagerie."

And right behind Lithgow, Katie Couric appears to examine Colbert's prostate, incase he has two.

But the guest stars don't end there. The Black Keys walk on to the set, instruments in hand, announcing, "A smooth prostate the size of a walnut, that's music to our ears."

Surprised at the turn out of guest stars willing to examine his prostate, Colbert jokingly lamented, "Due to the limited capacity of my colon, I can't fit you all in there. I'm going to have to make a choice, and tonight a highly dramatic latex glove ceremony. I want to thank all of you for going on this journey with me. But only one will be awarded this latex glove, which is a symbol of trust and also the actual glove you will use when you check my bungfruit for freshness. So make your final pitch, John Lithgow."

"Stephen, as star of Harry and the Hendersons, I stood face to face with a sasquatch, so whatever you've got going on down there won't frighten me."

It was Couric's turn to give her pitch. She declared, "Well, Stephen, as you might recall, I made TV history when I had my on-air colonoscopy on the Today show back in 2000. Well my experience and commitment are unparalleled. Plus, I just got a manicure, which combines the words "man" and "cure."

It was now The Black Keys turn to make their case. "Stephen, tonight I want you to think of us as The Brown Keys," Dan Auerbach said. "A two-man medical team. I'm the frontman so I'll conduct the exam."

"And I'll play the drums and not conduct the exam," Patrick Carney added.

After they had all given their case, it was time for Colbert to choose his examiner. "You're all so special. Any man would be lucky to have you examine his prostate for swelling lumps and/or suspicious texture. But of course, I have to decide."

Sadly (or actually, not), The Black Keys were passed over for the winner John Lithgow. "Come on Pat," Auerbach said. "Let's go check Jimmy Fallon's prostate."

Watch the whole scene here, and let us know what you think of it's ridiculousness in the comments section below!