Australia's former World No.1 has dropped out of the top 60, meaning he failed to gain direct entry, and opted out of this week's sectional qualifying event, preferring to receive treatment at home in Ohio for his chronic back injury.

Day hasn't missed a major since the 2012 Open Championship and has contested 10 consecutive US Opens since finishing second behind Rory McIlroy on debut in 2011.

Day's absence is the 33-year-old's latest setback following missed cuts at the past two Masters, the rescheduled 2020 edition in November and this year's in April.

He barely made the cut at last month's US PGA Championship, eventually sharing 44th spot – six years after hoisting the Wanamaker Trophy for his lone major championship triumph, then finishing runner-up in his title defence.

Day is a two-time US Open runner-up as well as a two-time PGA Tour winner at Torrey Pines, where he also won the World Juniors before turning pro.

But languishing at 107th in the FedExCup standings, he's now in a desperate battle to make the season-ending playoffs featuring the top 70 on the PGA Tour, and to be fit for next month's Open Championship at Royal St George's.

- Darren Walton, Australian Associated Press