In his first event since collapsing due to an attack of vertigo during the US Open, Day carded six birdies and no bogeys to outshine playing partners Louis Oosthuizen and Tiger Woods, winners of the last three Opens on the Old Course.
“I should just stay healthy so I don’t have to answer these questions any more,” joked the 27-year-old. “No, I feel good. I’m not thinking about falling over on my face again.
“I’m not worrying about it and I feel healthy, and I’m good to go.”
Day slumped to the ground on the final hole of his second round at Chambers Bay.
But after receiving treatment from paramedics the 27-year-old not only completed the hole, but shot 68 on Saturday to share the lead and went on to finish ninth, despite almost pulling out on several occasions.
He was diagnosed as suffering from Benign Positional Vertigo caused by an infection which had attacked and damaged nerves in his ear, and is now taking anti-viral medication.
“If it was the first time that I ever had it at the US Open then I’d be kind of scared coming out here knowing maybe it’s going to come back,” Day added. “But speaking with my docs and being on this medicine that I’m on right now definitely helps.
“I know if I have it, it takes a couple days to get rid of. Obviously it’s not great to have it in tournaments, but if it comes, it comes. I can’t really control it. That’s the unfortunate thing.”