Since the 50's, at the very least, television executives have figured out that comedians make the best game show hosts. From Jan Murray (Dollar A Second, Treasure Hunt) and Groucho Marx (You Bet Your Life) to Steve Harvey (Family Feud) and Wayne Brady (Let's Make a Deal), comedians have parlayed their stage presence and ability to connect with audiences into landing game show host gigs. Some have worked, such as the four mentioned above. Others, not so much.
One such example came in the fall of 1977. Ralph Edwards had been forced to move Name That Tune into syndication after two failed network runs. However, he sold another game to NBC that played off a familiar trope from Sesame Street, which I'll explain shortly. He hired actor-comic Arte Johnson (ex-Rowan & Martin's Laugh-In), who otherwise was working on the animated Laugh-In spin-off, The Nitwits, for the network when not appearing on The Gong Show, to host Knockout, which was also the first, and perhaps only, show that Jay Stewart, long associated with Monty Hall's production company, announced for Edwards.
That Sesame Street trope I referenced? Johnson would have four items appear on a video screen, and contestants had to figure out which one didn't fit with the others, which in turn would lead to a specific topic. Johnson's experiences as a panelist on Gong, Hollywood Squares, and CBS' Match Game had kept him in the public eye after Laugh-In had ended, and he looked so natural as MC. Unfortunately, he ran up against a brick wall in the form of a pair of Goodson-Todman games on the other networks, namely, Family Feud and The Price is Right, which ultimately led to Knockout getting knocked out after nearly six full months.
Let's scope a sample episode, which is the only one available, as it happens.