Johnson ready for long game in US Open double quest

Los Angeles : World number one Dustin Johnson is preparing for a battle of the big-hitters as he defends his US Open title next week on what is set to be the longest course in major championship history.

Johnson, who clinched his first major victory at Oakmont last year, has been installed as the favourite for the tournament, which is being held at Erin Hills in Wisconsin for the first time.

At 7,741 yards, the challenging par-72 layout outside Milwaukee will be the longest course in the history of major tournament golf.

United States Golf Association officials say the yardage may fluctuate, depending on adjustments to the set up which will be made based on the firmness of the ground and wind conditions.

But for Johnson, one of the longest hitters in golf, Erin Hills' potentially intimidating length augurs well.

The 32-year-old was perfectly positioned to win at Chambers Bay in 2015 -- until this year the longest US Open course in history -- only to three-putt on the 18th green of the final round to gift Jordan Spieth victory.

Yet he recovered from that setback to win at Oakmont last year, finally shaking off his majors jinx after a string of near-misses.

Johnson, who missed this year's Masters at Augusta after a freak accident on the eve of the tournament, revels in the US Open's reputation as the toughest test in golf.

"It's just a very, very difficult tournament to win," Johnson said. "It's always tough. Deep rough, greens are always firm and fast, generally. It's just a tough tournament to win."