Jack yesterday put pen-to-paper on a new deal keeping him at Ibrox until the summer of 2023 – and McAllister believes it’s just reward for his recent contribution to the cause.
Speaking at the Hummel Training Centre yesterday, McAllister said: “For me, he has been unbelievable from day one. He has improved no-end, and you are seeing a midfield player gathering loads of information, experience and being given a bit of responsibility he’s maybe not had in the past.
“You are seeing a player starting to play at the top of his game and it has been a pleasure working with him, and he deserves his new contract without a shadow of a doubt.
“He has been one of our main players since arriving here, and he is very influential, pretty robust, and his training performance as well is way up there.
“I think we saw a player who was just there to stop things and to break up play – maybe he was quite happy doing that.
“But, on arrival here, we could see he was capable of much more. Not only does he do that, but in most of our good build-up play, he is at the start.
McAllister, a long-serving Scotland midfielder in his day, sees no reason also why Jack can’t nail down a place in the national team in the coming months and years.
“Looking at our national team,” he added, “I think the strongest part is in the middle of the park. It is very competitive and there are a couple of players from Celtic who are doing very well, you have young John McGinn at Aston Villa who is doing very well and you have Scott McTominay at Manchester United.
“But, I think Ryan has a part to play. Steve Clarke knows what he does and I think he respects Jacko and I think he has a part to play for the national team.”