McAllister is understood to have lost three teeth and required 12 stitches in a facial wound after the incident in Leeds in the early hours of last Sunday morning.
West Yorkshire Police have confirmed they arrested a 32-year-old man in connection with what Gerrard described as a “horrendous” incident. He has been released while under investigation.
McAllister, 54, has been absent from training this week but he expressed his desire to return to work in time to be by Gerrard’s side in the technical area at Celtic Park tomorrow.
But Gerrard has instructed his No 2 to remain at home.
“Gary is recovering well and he is desperate to be back with us,” said Gerrard. “He wants to be next to me on Sunday and there’s no bigger game than the Old Firm. But I felt it was right to take the decision away from Gary for his own sake. He still needs a bit more recovery time mentally. From a physical point of view, there is still a bit of healing to do as well.
“I picked Gary as my right-hand man for a reason. For his knowledge and his education in the game. He’s been a massive help for me up until this point. But there would be a downside to dragging him back too early for my own sake at this point. I’ve got to think about Gary and the bigger picture. The sensible thing is to give him more recovery time but we will still be using him in the build-up to Sunday. I’ll speak to him on the morning of the game and I’m sure he will be sending information to us.
“What happened to him was horrendous. I woke up to eight missed calls from him so I knew there was a bit of a problem.”