Hughes, appointed in midweek as the club's new manager following Neale Cooper's recent resignation, saw his new side crumble against Mark Robins' side.
All the goals came in the second-half, the first three in just eight minutes as Pools collapsed to a humiliating defeat. They started positively, but after failing to score soon went back into their shells.
"This has identified some issues for me - a real baptism of fire," said Hughes, who moved to Pools from Scottish First Division outfit Livingston. "Two things I'm disappointed about - our heads went down when we conceded and of course the result.
"One goes in and we have something. First 30 minutes we had the excitement of a new manager, a lot of it off the cuff by design.
"Then they got their foot on the ball and came right into it by design. They got one, our heads went and confidence went and they won convincingly - it's a great disappointment."