Translation of "Guard's" in Japanese

The guard's truncheon hit air. Off balance, he regained his posture to see a metal-mesh rubbish bin flying towards him.

警棒で空をなぐりつけ、よろめいて体勢をたてなおしたガードマンは、自分に向かって突進してくる金網づくりのクズカゴを見た。