The accident Friday halted production of "Tonight," NBC said. The network did not say what the stunt entailed.
O'Brien was examined at a hospital Friday and was released, although the network didn't say when.
A "Tonight" rerun with guest Jeremy Piven aired Friday. According to NBC's Web site, the scheduled show was supposed to include actress Teri Hatcher and Seth McFarlane ("Family Guy," "The Cleveland Show"). Actress Drew Barrymore and jockey Joe Talamo were the scheduled guests for Monday.
O'Brien, 46, issued a statement through NBC that indicated he was treating the incident lightly.
"Last thing I remember I was enjoying the play with Mrs. Lincoln, and the next thing I knew I was in bed being served cookies and juice" O'Brien said in the statement.
The accident brought back memories of a rare absence by his predecessor. O'Brien took over the "Tonight" host's job from Jay Leno in June.
Leno's absence came toward the end of his 17 years with the show, when a high fever and unspecified illness caused him to check himself into a hospital for a day. NBC canceled two episodes of "Tonight" when that occurred in May.
NBC's decision to remove the top-rated Leno from "Tonight" and replace him with O'Brien, hoping to draw a younger audience, put pressure on the new host's shoulders.
The network's creation of a daily prime-time comedy show for Leno, displacing five hours of scripted shows, was another bold move. Leno's new show debuted this month.
NBC is owned by General Electric Co. ---
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