This is exactly what Sentinel did with Megatron, how amusing. When Impactor connects, he digs his heels in and manages to avoid being completely floored, though still gets robo-winded. Now who's the annoying freakish giant, Shockwave??? (It's still Sentinel).

He elbows Impactor sharply in the back, seeing if he can get him down again. It's very tempting to just shoot him but being on probation and all...