J.K.
He's too little for wrestling. And there's no reason he should be hitting anyone ever. I would nix it until he's older and then get him into karate. When I say not to let him wrestle, I don't mean not to play with him physically. Change the game so he can run to you catch him as he knocks you over, but then sometimes he can't knock you over. You get him, but sometimes let him get away. Make sure that he knows he can't just ram into you and knock you over without warning, and no hitting, slapping etc... You set the boundaries. This is physical enough at this age will teach him some valuable skills about boundaries and strength. And I make sure he also knows that this is a game we play with Mommy or Daddy, not with other kids.
Good luck