Ponte Vedra Beach - Jason Day has withdrawn from the Mexico Championship because of an infection in both ears and the flu.
The elite $9.75 million World Golf Championship, to be held in Mexico City this week for the first time and featuring the highest altitude for a PGA Tour event, was poised to have all the top 50 golfers in the world.
Day is No 2 in the world.
"I'm truly disappointed to announce that I won't be able to play in next week's World Golf Championship-Mexico Championship," said Day in a statement, as quoted by the PGA Tour.
"I have a double ear infection and the flu, which precludes me from preparing for and playing in the tournament. I have heard great things about the Mexico Championship and the golf course.
"I want to thank the Salinas family for their support of the event. I look forward to teeing it up there next year."
Day lost his top ranking last week to Dustin Johnson, who won the Genesis Open at Riviera Country Club last weekend.
Day says the ear infections and flu have kept him from preparing properly.
This will be the first World Golf Championships event that the 29-year-old Australian has missed since the Cadillac Championship at Doral three years ago.
He was coping with a thumb injury that year.