Maxwell, who was previously part of the youth set-ups at Ayr United and Falkirk before joining Rangers, has put pen to paper on a season-long loan deal at Palmerston Park.
The-18-year old follows in the footsteps of fellow Gers academy graduate McCrorie in joining the Scottish Championship outfit, with the young shot-stopper spending half of the 2019/20 season with the Doonhamers.
Johnston, who welcomed the addition of Maxwell to his squad, is hopeful that the full-back can shine at his new stomping ground and develop his game just as his predecessor McCrorie did last term.
The Queen of the South boss expressed his gratitude to Rangers for lending their young talent to his team and the 46-year-old has backed the teenager to flourish at his new home.
“Left back wasn’t an area that we had prioritised but following the departure of Kevin Holt we had to look for a replacement”, Johnston told Queen of South’s official site.
“We are grateful to Rangers for agreeing to let him join us.
“We hope he does as well for us as Robby McCrorie did and we can help him develop.”
Maxwell who made the leap up to the Gers’ development squad from the Under-18s last summer, is now on his maiden loan spell away from Ibrox.