Singer-actress Kristin Chenoweth was the guest judge on last week's premiere episode of the show.
Adkins will appear on Friday's edition as the contestants receive their second challenge.
"The nine remaining contestants are grouped into trios," CMT said in a news release Wednesday. "They are to perform outside on Nashville's famed Lower Broadway for the citizens of downtown Nashville, playing for nothing but tips. The trio that receives the fewest amount of tips is forced to 'sing to survive' later that night at a honky-tonk. One more contestant is eliminated."