The crunch is the sound of satisfaction, but it's a very fleeting moment. He underestimated the force of his kick in his weakened state, he'd been relying on knocking Gannicus over. Instead, he's angered him and Nasir is closing in, preventing him from moving away from the act of vengeance of the crowbar.

It hits its mark without any wavering, Thor feels like his eyes have been knocked out of his skull from the force. Luckily, his skull is tough enough that the single hit would not kill him, but the dizziness and darkness filling his mind comes quickly. He slumps forward, hitting the ground with a thump, entirely down for the count. For now, anyway.