Why is Jason Day so annoyed at himself?!

Jason Day believes he has “severely underachieved” so far in his career – but is determined this will be the week that starts to turn around.

Speaking ahead of this week’s US Open at Pebble Beach, the Aussie delivered a withering self-assessment, despite being a major winner, multiple PGA Tour winner and former world No.1.

“I feel like I’ve severely underachieved,” said the 31-year-old. “I feel like I’ve got a game that when it’s on, I can win most tournaments. And the big thing for me is to go ahead and believe that and have trust in my abilities that I can do that.

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“I know that I can do it. All you have to do is look at 2015, 2016, even last year, not just have a single season win. I know that I can have multiple wins in one year and I can get things going.

“So I just have to get that desire back into my game and keep working hard.”

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That withering self-assessment explains, in part, why Day has hired Steve Williams. The man who caddied for Tiger Woods during 13 of his 15 major victories is picking up the Aussie’s bag, beginning at this week’s third men’s major of the year.

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“Now that I have Steve on the bag, I think hopefully that will flourish and I can make winning more of a habit,” he added. “He thinks that I’m an underachiever and he wants me to win a lot more tournaments. I think that he has the ability to get me through the line a lot more and being able to turn my game around.

“To be honest, I’m kind of in like a little bit of a mini slump, even though I’ve had some good finishes. I feel like I need to win a lot more and I think he’s got the formula to be able to hopefully get me across the line a lot more and win some more tournaments.”

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