If the thunder and lightning can skip around Erin Hills this week the U.S. Open should be fascinating. Tough and uncompromising, but fascinating.

Erin Hills is set up to play to 7,741 yards—the longest course in the history of major championship golf (although it could top 8,000 yards if the USGA so wanted)—but with firm-running, linksy fairways the course is not designed to play as long as it looks. However, there is a high chance of showers over the first three days of the tournament this week, probably accompanied by some jagged electricity, so the run on the ball could be tapered to present the players with a long-game battle of a new kind.

The USGA has pushed the fairway landing areas out so they are wider than you might expect of a typical U.S. Open, but the sense of forgiveness ends there as the tall fescue rough beyond the fairways is long and thick—reminiscent of the [British] Open at Carnoustie in 1999—and when that tall grass gets weighed down with rainwater, staying clear of it will be critical.

The long and the short of this golf course and the likely conditions could play into the hands of the defending champion and world number one, Dustin Johnson. With his prolific length and accuracy off the tee, if Johnson can find his groove this championship could be all but over by the time the weather clears up, as it is forecast to do for the final round on Sunday.

But Johnson does remain a big ‘if’ since injuring his back in a fall down the stairs on the eve of the Masters in April. In the build-up to the Masters he was untouchable, winning all of his previous three appearances, but since his recovery and return to tour golf Johnson’s form has been changeable, like the shies above Wisconsin, and he missed the cut on his last outing at the Memorial at Muirfield Village.

If Johnson falters look out for Rickie Fowler, who is desperate to bounce back after a disappointing final round in the Masters, and if the rains do soften the greens a little it could open the way for great long-game strikers like Adam Scott, Justin Rose and young Spaniard John Rahm. Heck, those conditions might even suit Masters champ Sergio Garcia. Can lightning strike twice? It probably will this week at Erin Hills, literally, so don’t count out Garcia too soon.

Erin Hills is a modern course with a traditional feel—having opened in 2006—and which was built with the specific ambition of hosting major championships. The design saw collaboration between Michael Hurdzan, Dana Fry and Ron Whitten, and the trio has made spectacular use of this 652-acre expanse of Kettle Moraine post-glacial terrain, which is hemmed in by wetlands and the Ashippun River, 35 miles to the northwest of Milwaukee. What is more, Erin Hills was created as a course to be walked, which is refreshing in this age of cart-crazed golf in America.