Images from Jason Day, who collapsed on the final hole of his second round at the U.S. Open.
Jason Day of Australia is tended to by caddie Colin Swatton as he lays on the ninth green after falling due to dizziness during the second round of the 115th U.S. Open Championship at Chambers Bay on June 19, 2015 in University Place, Washington. (Photo by Harry How/Getty Images)
Jason Day of Australia is overcome by dizziness and lays on the ninth hole as his caddie Colin Swatton looks on during the second round of the 115th U.S. Open Championship at Chambers Bay on June 19, 2015 in University Place, Washington. (Photo by Ezra Shaw/Getty Images)
Jason Day of Australia is tended to by caddie Colin Swatton as he walks to play a bunker shot on the ninth hole after falling due to dizziness during the second round of the 115th U.S. Open Championship at Chambers Bay on June 19, 2015 in University Place, Washington. (Photo by Ezra Shaw/Getty Images)
Jason Day of Australia stands up after falling on the ninth green due to dizziness during the second round of the 115th U.S. Open Championship at Chambers Bay on June 19, 2015 in University Place, Washington. (Photo by Harry How/Getty Images)
Jason Day of Australia walks across the ninth green during the second round of the 115th U.S. Open Championship at Chambers Bay on June 19, 2015 in University Place, Washington. (Photo by Harry How/Getty Images)