McGill, 20, was knocked unconscious when he collided with a Torquay player during a remarkable first-round clash at Plainmoor, which Crawley won 6-5 after extra-time.
The tie was delayed for 18 minutes as the stricken McGill received treatment on the pitch by Crawley physio Harry Brooke. He was taken to Torbay Hospital but released later that day.
“It looked like a through ball I could go for," said the Canadian born keeper. "I came out, spread myself and then the next thing I remember is the physio Harry (Brooke) standing over me.
“I don't think I blacked out for too long but, looking back at the replay, the Torquay players were really good. They got Harry on straight away, so I am thankful for that.
“I came round while the physio was standing over me and remember him checking my neck was okay, but it was all a bit blurry. I was then put in an ambulance and taken to hospital.”
Crawley's general manager Tom Allman accompanied McGill to hospital. They managed to keep in touch with the epic FA Cup match which ended 3-3 after 18 minutes of stoppage time.
Torquay went 5-3 up in extra time, but Crawley somehow scored three goals to go through.
“It's just as well that I was down for so long because it gave the boys enough time to come back," McGill joked.
"When I went off it was 2-0 and Tom [Allman] came to the hospital with me and was getting updates on his phone, it seemed like every couple of minutes at one stage!”
McGill hopes to get back playing soon and continue his loan spell with Crawley but will have to follow FA concussion protocols.
“With the number of players who can't get a contract I think it’s tougher now to even get a loan spell than it has been so to be here at a local club and playing in cup games at least is something I couldn't turn down.
“It's a lot different playing men's football to academy football. The gaffer here [John Yems] likes to try and play and I am enjoying myself.
"We've got a good group and the season has started pretty well. The more experiences you have of different playing styles the more it will help you in your career.”