"What do you mean, 'go back?'" Philbin asked. What proceeded was a back-and-forth between the two men where Letterman tried to explain that he meant for Philbin to go back as a guest on "Live," while Philbin thought he meant go back as a co-host.
Finally, Philbin said he wasn't sure if he would go back, even if he were invited as a guest. Thus far, he hasn't been asked on.
"You know [what] the problem with this [is]? That [Michael] Gelman. I never liked that guy from the beginning!" Letterman joked, prompting Regis to defend his longtime producer.
That doesn't mean Philbin can't be seen during the day, though. His fans can check him out when he co-hosts "Rachael Ray" once a month.
Correction: An earlier version of this post incorrectly attributed Letterman's Michael Gelman joke to Regis Philbin.
Tune in every weeknight at 11:35 p.m. EST on CBS for "Late Show with David Letterman."
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