US Open: Defending champion Dustin Johnson makes early exit

Dustin Johnson vowed to work hard on his putting and expressed his disappointment that his defence of the US Open title ended with a missed cut.

Johnson insisted he was happy with his long game at Erin Hills, but he could not back up his ball striking with his putting as he failed to build on a positive start to his second round.

The defending champion was up against it after his opening 76, but he made early strides up the leaderboard with birdies at the first two holes before missing a series of further chances on the front nine.

Johnson bogeyed the ninth and got the shot back at the 12th, but bogeys at the next two holes dropped him back to three over and another dropped shot at the 17th sealed his fate.

"I hit the ball better than I did yesterday, I drove it very well and hit a lot of good iron shots, I just didn't make any putts," said the world No 1, who's four over score was three too many to make the weekend.

"I birdied the first two holes, but those were tap-ins. I missed another one on four from about three feet, but I didn't feel like I was hitting bad putts, I was just misreading them. I don't know what else it was.

"It was a surprise as I really like this golf course. It sets up really well for me, especially if I'm driving it like I did today. I couldn't possibly shoot any higher than I did, I just struggled on the greens. This game's all about putting, so it's pretty simple, I just didn't get it in the hole fast enough.

"It's just golf and it's frustrating, but I don't let it bother me. I feel like the golf game is there, I feel like I'm playing good. I've got four weeks off now and I'm looking forward to it very much," added Johnson, who became a father for the second time last week and will not play again until The Open at Royal Birkdale.

"I'll work on the game a little bit, and I'll be ready to play at the British. I need to practice a little bit and I need to work on my putting mostly. But I'll play a lot, I just won't practice too much. I'll probably just play for sure to get ready for the British.

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"This is the United States Open, it's a major and it means a lot to me. I'm definitely disappointed I'm not playing the weekend, but there is a lot I can take out of it. I feel like I'm striking it very well, so I just need to go home, relax a little bit, hang out with the family and I'll see you at the Open Championship in a month."