The former Weeds star visited the dentist prior to his chemistry read with LeBlanc and initially thought he would have enough time to recover in between the appointment and his TV meeting.

However, the dentist visit took longer than expected and the numbing agent Nealon was given didn't wear off before his audition.

"I'm in the dentist chair and they find a little extra work they have to do so they have to give me more Novocaine," he told Live! with Kelly on Friday (09Dec16). "So I'm kind of back, upside down, and the whole side of my face is numb and I said, 'I got to really get to this audition, I have a chemistry read'."

Instead of trying to reschedule the meeting, Nealon rushed to the audition, and while he didn't think it went so smoothly, LeBlanc actually enjoyed it.

"They finally get me out of there (the dentist's office) and I'm driving like crazy to the audition and I'm trying to un-numb my face," he continued. "I get there and I'm still numb and Matt LeBlanc comes into the room and we do a little practice read. And he told me in hindsight he went back to meet the producers afterwards and they said, 'How is he?' and he said, 'Well, he's a little shaky in the lines, but his timing is perfect and I think he may have had a stroke!'"