I would have never expected to ever see him as a character in the Mario Tennis games.
Obviously he's a in the power class, which makes him very difficult to defeat if you're the one facing him. Like Bowser, Chain Chomp's defense relies on his large size taking up half the court, making it easy to hit the balls back into the opponents court.
I had some rare losses with him, but he was among my top in the game. My personal favorite next to Bowser.