The goalkeeping great, who was inducted into the club’s prestigious Hall of Fame earlier this season, will become the first player to break the 500 barrier since Ally McCoist, and be just the 16th player in history to reach the milestone for Gers.
McGregor’s second spell at the club began in-tandem with manager Michael Beale’s first period at the club – and he has been paying tribute to McGregor in an exclusive RangersTV sit-down interview ahead of what could be – if he is in the XI – an historic day for McGregor.
Beale told your club channel: "Allan rejoined the club and I joined the club for the first time in the summer of 2018 and I hadn't worked with him before, but quickly I saw how fantastic he is day-in, day-out in-terms of his work ethic and his training and his rituals.
"He is a man that sticks to his rituals and works away - if we are a minute late to the stadium he gets annoyed as he is really thorough in his preparation, his recovery and his training.
"That has enabled him to have a wonderful career. To achieve 500 games for Rangers is a very special achievement - very few have done it in the past and certainly, to the age that Allan has played and the achievements that he has had for the club.
"In the time I have worked with him here, he has been absolutely outstanding - some of the saves that he has made, there are too many to mention but every season he has earned us points, he has won us games and he has got us through to the next round in cup competitions.
"I think he can be hugely proud - he's not finished yet - so it will be 500 and something - it won't be 500 and it won't end there, but I think the service he has given this football club as a young boy coming through our Academy is absolutely outstanding."
Beale added further praise for McGregor’s influence around the club, and reckons every member of the first-team squad should look to him for inspiration in their careers.
The manager continued: "I think when you look at him day-in, day-out, there is no secrets - it is hard work, preparation and dedication to your craft.
"He is always intrigued and open-eyed in-terms of learning and wanting to get better - this is a man in his 40s who trains every day like he is a teenager and he is watching and he is learning all the time.
"He is very self-reflective and very self-critical if you like - he is willing to take feedback on and he just wants to win and get better.
"If that can't rub off on you as a young player - and to be honest, everyone in the squad is younger than him - if that can't rub off on you then you aren't opening your eyes to bettering yourself.
"I think Allan has been a cornerstone to everything that has been good about this club since I came in 2018."