Day out of Australian Open, Presidents Cup

Darren Walton
Jason Day has been ruled out of the Australian Open and Presidents Cup with a back injury

In a major disappointment, Jason Day has been ruled out of the Australian summer of golf with a back injury.

The former world No.1 will miss next week's Australian Open in Sydney and then the Presidents Cup in Melbourne after being advised to shut down his season.

International captain Ernie Els has replaced Day with South Korean An Byeong-hun as his team of heavy underdogs attempt to beat the powerhouse USA outfit for the first time since 1998.

Day, set to play his fifth Presidents Cup, was a captain's pick for the December 9-15 biennial event at Royal Melbourne Golf Club where the International side, representing the rest of the world minus Europe, face a US team led by Tiger Woods.

"We wish Jason well and hope his back recovers quickly," Els said in a statement. "We were eager to have Jason as part of the team at Royal Melbourne and his experience will be missed.

"The good news is that there were a number of strong and qualified players available to choose from when I made my captain's selections.

"To have someone as steady and talented as Ben An puts us in a great position to succeed."

"I'm quite disappointed I won't be coming home to play in either the Australian Open in Sydney or the Presidents Cup the following week in Melbourne," Day said in a statement.

"I was quite looking forward to both events.

"I had been prepping all week in Palm Springs when I was injured. Frustratingly, I've been through back problems before and my medical team decided it best to shut down all practice and play."

An had three top 10 finishes on the PGA Tour last season, including a third-place at the Wyndham Championship in August.

The South Korean has enjoyed a hot start to the new season with third place at the Sanderson Farms Championship and ties for sixth at the CJ Cup and eighth at the Zozo championships.

"It was a huge surprise to receive a call from Ernie who told me that I was in the team," said An, the son of two Olympic table tennis medallists.

"It has been a goal of mine all season to be on the International Team and I am honoured to play in my first Presidents Cup."