Dustin Johnson, US Open 2017, golf, second round, cut
The world number one Dustin Johnson made an early exit from the US OpenRoss Kinnaird/Getty Images

Paul Casey rode a rollercoaster to a four-way share of second-round lead at the US Open on Friday, but it was the end of the line for the world's three top-ranked players.

Among the early starters on another steamy day at Erin Hills, Casey survived a hair-raising round that included a gut-wrenching triple-bogey and a thrilling run of five straight birdies and ended with him signing for one-under 71.

The Englishman then sat back and watched as compatriot Tommy Fleetwood and Americans Brooks Koepka and Brian Harman each carded two-under 70 to join him at the top of a crowded leaderboard at seven-under.

Lurking one back are a trio of Americans Jamie Lovemark (69), JB Holmes (69) and overnight leader Rickie Fowler, who slumped to a one-over 73, carding three consecutive bogeys in a back nine retreat.

It was day of sizzling drama on the links-style layout that featured stunning birdie runs and spectacular collapses – some like Casey coming on the same scorecard.

The biggest jolt of all, however, came watching world number one and defending champion Dustin Johnson, number two Rory McIlroy and number three Jason Day all trudge to the exit after failing to make the halfway cut, which fell at one-over 145.

It marked the first time since the world rankings were created in 1986 that the top three ranked players in the world missed the cut at a US Open.

Johnson, who arrived late at Erin Hills following the birth of his second child on Monday, will now have extra time to spend with his infant son after returning a 73 for four-over.

Day, who had made the cut at every major since the 2012 PGA Championship, followed up his opening round 79 with a 75, leaving the Australian anchored near the bottom of the leaderboard at 10-over.

McIlroy, sidelined for a month with rib and back injuries, could not shake off the rust missing the U.S. Open cut for the second consecutive year.

The Northern Irishman closed out his round in style with four birdies over his final six holes for a 71 but it was a case of too little unable to undo the damage of a first round 78.

Paul Casey, US Open 2017, golf, leaderboard, score
Paul Casey overcame a major blip to head to the top of the leaderboard, June 16, 2017Reuters

Casey, who began the day one shot back of Fowler, found trouble when he flew his approach out of rough over the green at the par-five 14th, his fifth, into the deep fescue and needed five more strokes to get in the cup.

A rattled Casey added another bogey at the 15th to extend his miserable run before hitting the turbo-charger and firing off five consecutive birdies.

"Not every day you enjoy a round of golf with an eight on the card, but I'm a pretty happy man," said Casey. "It was a bit of a roller coaster."

After an opening round 74, world number four Hideki Matsuyama looked ready to join the parade of top ranked players to the exit but the Japanese hit back with the joint best round of the day of seven-under 65 to shoot up the leaderboard and into contention at five-under.

Joining Matsuyama two shots back is an eclectic mix that includes PGA Tour rookie Xander Schauffele (73), amateur Cameron Champ (69), 36-year-old PGA Tour veteran Brandt Snedeker (69) and 21-year-old South Korean Kim Si-woo (70), the youngest player to win the Players Championship.

Get the full leaderboard of US Open 2017