His grin broadens even as his shell impacts with the ground. Then Donnie throws the punch and he reaches to grab his fist. "Now we're talkin'!"

Despite what little wriggle room Don's left him, he tries his best to wrap his legs around Don's and push himself off the ground with his free hand. He'll use his superior strength to try to roll his brother off of him and wind up on top, hopefully pinning Don to the ground.