But on Thursday, he revealed how he got her back at her ... by filling her SUV with 20,000 ping pong balls!
"Damn, you, Lauer! He's littering. This is against the law!," Ellen yelled as she opened the car doors to free the balls.
After she was handed an iPad, Matt proceeded to tease the comedienne. "What is that behind you? It looks like a real mess," he said with a laugh.
"Hilarious, but I suggest you watch the show tomorrow because I got you again today on the show I just did," she warned. "Now it's on. Before it was fun and games, it was jokes. But now it is on, Lauer."
Check out the clip above to see Matt's sweet, sweet revenge.
We can't wait to see how Ellen retaliates, can you?!