Three-time Masters champion Phil Mickelson has claimed that he is puzzled by his form at Augusta this week after missing the cut for the first time in 17 years.

Having carded an opening round of 76 on Thursday, the 43-year-old suffered further turmoil on Friday after hitting a triple-bogey on the par-three 12th to miss the weekend for the first time since 1997.

"Why couldn't I get it going? You know, I don't really have a great answer for you," he told reporters.

"I've actually played reasonably well for a majority of the holes and then the ones that I let slide I end up making a big number. So it's tough to overcome those big numbers.

"What happened at 12 was I hit in the front bunker. And there was no sand where I was at. I caught the liner of the bunker and bladed it across the green and the same thing happened on the other side."

2012 champion Bubba Watson currently leads the way on seven-under, three strokes clear of Australian John Senden.