O'Brien caught the eye in victory over Fulham.
Allardyce told whufc.com: "I've got to give a great big boost to Joey O'Brien. He was one of the best young players I ever worked with when I was at Bolton. Injuries have dogged his career but I asked him to fill in at left-back against Fulham and he gave the kind of performance that I saw many years ago. I hope for him that he keeps that up.
"There were a lot of people who had forgotten about Joey in the game and playing like he did against Fulham will get people to sit up and take notice. I hope he continues that kind of form as the season progresses."