Agile as he was, he was still a scrawny little teen. There was very little chance he'd actually be able to overpower the man in a struggle to pin him. So he didn't try for that.

Instead, before he himself could be pinned, he flailed his fists in an attempt to land a blow on the other's face. It was a rather childish move, but he didn't have too many other options at this close range.