The Jimmy Kimmel Live! host, 47, detailed Arnett's trick on his talk show on Thursday, April 2, explaining just how much the prank ruined his day.
"I wasted so much time today, it's amazing I was able to even get dressed for the show," Kimmel began. "I got a text this morning from Will Arnett... This is from Will, it says, 'Dude... It's Arnett. As a parent you'll appreciate this...'"