Willett capitalised on a dramatic collapse by Jordan Spieth to win the Masters last year, the Sheffield man compiling a flawless closing 67 to become the first English winner at Augusta National since Nick Faldo in 1996.
The 29-year-old also finished third in the BMW PGA Championship and second in the Italian Open, but was struggling for form by the time of his Ryder Cup debut and failed to win a single point, albeit not helped by his brother’s controversial article about American fans.
So far in 2017 he has failed to convert a three-shot 54-hole lead in Malaysia, become the first defending champion since Mike Weir in 2004 to miss the cut at Augusta and split from his caddie mid-tournament.
And from a career-high of ninth in the rankings, Willett will arrive at Erin Hills on the verge of dropping out of the top 30, a position he has not occupied since the 2015 Open Championship.
Asked if playing the US Open without the burden of being a reigning major champion would help lower expectations, Willett said: “We’ve had a little dip in form and I think the expectations from other people come off you pretty quickly.
“It’s more the expectations of yourself really and what you put yourself under. I know what I can do and unfortunately I’ve not been doing it. That’s where the frustrations lie.
“It’s been a pretty crappy start to the season but it’s now getting to a really busy stage where there’s a lot of big tournaments coming up, so over the next three months there is a lot up for grabs if we can get back somewhere near and have a few nice finishes.
“You want to be able to push yourself forward and make a run for it at the end of the season. It’s an important few months coming up.”
Willett did at least make the cut in the BMW PGA Championship at Wentworth after being forced to withdraw from the Players Championship with an ongoing back problem.
But he admitted there was “no point” in entering any other tournaments before the US Open if he does not feel he can compete at the highest level.
“We’re working hard, it’s just not quite where we want it to be,” Willett added. “We’ve had a lot of weekends off to rest and think about it so it’s really just about making sure we keep working hard and we can find something.
“There’s no point in pitching up and playing in an event where you don’t feel like you can compete and win - you want to play when you are fresh and ready to play and you’ve got a chance of winning.
“With how things are and where the golf shots have been and where the misses have been, I struggle to see me being in contention so therefore I needed a couple of weeks to get back to where you feel like you should be.”