During the first decade of Sesame Street, a common feature of Kermit's Lectures was Grover's unwanted help. Grover would make his presence known as he strolls by in the background and taking notice of Kermit as he speaks to the audience. Grover would then run up to him screaming, "Hey, froggy baby!" and giving him a rather hard black slap, usually propelling Kermit forward. The gag became frequent enough that variations by Kermit were soon done.
- A 1969 sketch with a Grover-precursor features the earliest-known version of the gag, having the monster appear beside Kermit, saying "Hey there, frog!" and giving him a tough pat. The first sketch where the proto-Grover earns his name also features the gag.
- A 1970 appearance on The Ed Sullivan Show (featuring one of the earliest appearances of Grover, just following the finale of Season 1) has him yelling, "Hey, froggy!" and slapping him on the back.
- A Season 2 segment features Grover helping Herbert Birdsfoot demonstrate over and under. Before the lecture, Grover gives a hard slap on Herbert Birdsfoot's back. It causes Herbert to cough, making Grover think that he has a cold.
- Grover slaps Kermit's back at the beginning of a sketch about Heavy and Light.
- A Sesame Street News Flash segment on what makes people angry features a cameo by Grover. This time, Grover gives Kermit a slap on the back as he exits the scene.
- A season 4 sketch has Kermit ducking out of the way just as Grover tries to slap him.
- In an appearance on The Electric Company, Grover gives J. Arthur Crank (Jim Boyd) a slap on the chest upon arriving at Vi's Diner.
- The Electric Company crossover special Out to Lunch features Reporter Kermit getting a slap from Grover Knover before he begins his interview.
- Grover delivers one to a prop letter S in a Muppet & Kid Moment with Debo, which causes the letter to fall off the wall and break. "I hope he did not take it personally," he states.
- A season 9 segment features Grover performing a lecture. This time, Kermit rushes up to him, yelling "Hey, Grover baby!" and giving him a slap on the back. In the second part of the segment, Kermit appears to do it again, with Grover gearing up for the slap, only for Kermit to stop just before and casually greet him.
- Appearing on Dinah! in 1977, Dinah Shore asks Kermit what he would like for his birthday, and Kermit asks that he not get hit by Grover as a greeting. This leads to Grover demonstrating the routine, and he asks Dinah how he could ever give up such a gesture of affection.