Having collapsed on the final hole of his second round on Friday after being overcome by a bout of vertigo, it was uncertain whether Day would be able to play on Saturday. However, not only did he play, but he surged into a share of the lead.
It was clear to see that Day was struggling at Chambers Bay, with the world number 10 appearing fatigued and frail. Speaking later on Saturday, the 27-year-old revealed that he had struggled with dizziness, nausea and shaking during his third round.
Day birdied three of his last five holes to take a share of the lead in a gutsy display that has been rightly lauded.
Day's fellow pros led the praise…
— Luke Donald (@LukeDonald) June 21, 2015
WOW! What Jason Day is doing is incredible! He still doesn't look anywhere close to 100% but he is one tough Aussie!
— Billy Horschel (@BillyHo_Golf) June 21, 2015
Jason Day is putting in a heroic effort. Much respect deserved.
— Joe Ogilvie (@ogilviej) June 21, 2015
From today on, @JDayGolf is one of my heroes… What a fight against his illness… Big lesson to those people who quit for nothing…
— Pablo Larrazabal (@plarrazabal) June 21, 2015
Jason Day reminding me of Ken Venturi…..
— Trevor Immelman (@TrevorImmelman) June 21, 2015
— Morgan Pressel (@mpressel) June 21, 2015
Day's compatriots joined in too…
— rennae stubbs (@rennaestubbs) June 21, 2015
— Shane Warne (@ShaneWarne) June 21, 2015
Day's wife was, not surprisingly, one of those to congratulate the Queensland native…
My phone! My heart! My husband! @JDayGolf you. Are. The. Man.
— Ellie Day (@ellielaneday) June 21, 2015
The last word goes to Day's caddy, Colin Swatton…
"Jason almost quit three times on the back nine," said Swatton.
"That was superhuman effort. That was the greatest round I've ever watched.
"They're going to make a movie about that round. It was pretty impressive, it was up there with Tiger Woods playing with a broken leg at the US Open [in 2008].
Swatton added: "I said you've got the heart of a lion. You're going to show the world today you're going to be the greatest you can be."
"He said, 'Let's do it' and he just put his head down and kept walking one foot in front of the other."