Maggie was admitted to hospital after suffering a seizure and was found to have mycoplasma meningoencephalitis - a form of meningitis which causes swelling on the brain.
The teenager fell into a coma for almost three months during which time she was moved every two to three hours to prevent her limbs stiffening up.
To remind her of who she was, the family placed a basketball in Maggie's hands when she was seated upright in a wheelchair, roped in to the chair for safety.
Amazingly, the young woman's reflexes kicked in and she started shooting hoops.
Dr William Graf, Meier's neurologist, told thedaily.com: "The act of shooting a basketball must have been ingrained as one of Maggie's basic instincts - her basketball shooting motion came back to her even before she was able to stand up or walk again."
During Maggie's time in hospital, she would shoot a few hoops, then fall back into a comatose state.
Since coming out of her coma, the high school student has had to relearn every facet of her daily life - how to walk, speak and read. And improve her game.
While she was in hospital, Maggie's fellow players on the school team, The Huskies, and coach David Glenn kept a chair by the court which said "reserved for Maggie Meier" on the back.
On Monday, she returned to the court after almost four years spent recovering.
She said: "When I'm out there, I don't think about it that much... But when I do think about it, it's pretty awesome."