A bunker mentality could prove crucial for Graeme McDowell and Shane Lowry at Congressional.

Congressional’s traps appear to have been filled with extra sand to make them a scarier hazard than ever. And that could give the Irish pair an edge of the field in what could become a survival test over the next four days.

McDowell said: “Bunker play this week is huge. I spent a lot of time in the bunkers yesterday and they going to play a huge part. Balls are flying in and they’re plugging every time. It’s very severe.

“We’re spoiled generally. Bunkers are so well prepared, they’re firm, they’re easy to play and I actually prefer a bunker shot a hell of a lot more than playing out of the rough. This week I’m not so sure.”

Lowry calls the bunkers his playground and he’s hoping he continues to have fun in the sand this week.

Like Lowry, McDowell is one of the best bunker players around.

But he knows that he has his work cut out this week, explaining: “There are going to be a lot of players this week who do not like this sand. It is soft and I’m having to play a lot more bounce out of the traps this week.

“You’ve got to really lay that sand wedge open and try and use the bounce as much as you can.”

His bunker play will play a huge role in his bid to become only the second player to retained the title since Ben Hogan in 1951.

But McDowell still believes he has a chance to emulate American Curtis Strange, who successfully held on to the trophy back in 1989.

He said: “The chances are about 40-1 according to the bookies, but it’s nice to be here at a US Open set-up believing that I can win because I’ve already done it.

“It is an interesting feeling playing the golf course yesterday and knowing that if I’m playing my game I can contend this weekend. That’s what it’s all about for me.

“Thursday and Friday are all about positioning myself, giving myself a chance this weekend. There’s some great players here this week and I just want to be one of the guys in with a shout come the weekend.”