Charlie Beljan said he had to dig deep to fight off health concerns and keep his lead in the Children's Miracle Network Hospitals Classic.
Returning to the course after an overnight stay in hospital following a panic attack so severe that he struggled to breathe and feared for his life, Beljan fired a one-under 71 to secure a two-shot lead going into Sunday's final round.
"I honestly didn't think I was going to get through it," Beljan told reporters after the round. "I just stayed strong."
Beljan, who is fighting to save his PGA Tour card, started the day with two bogeys in the first three holes and also said he started to feel some of the same symptoms from Friday as he approached the turn.
But he managed to calm himself again and five birdies on his card ensured his three-shot overnight lead was only reduced by a single stroke.
"It's nice to be able to walk around and smile," Beljan said after perking up on the back nine. "Yesterday, I was hanging on for my life."
This event is the final one of the 2012 PGA Tour season and Beljan needs to jump 14 spots to make the top 125 and secure his card for 2013.
It's that goal which has driven him on this week when he probably would have pulled out under normal circumstances.
A top 10 finish would likely be enough for him to achieve his goal although the prospect of a fairytale victory remains very much on the cards after he came through Saturday's test.