Rory McIlroy in Danger of Missing Cut at 2017 US Open After Nightmare Start

Rory McIlroy, who unraveled with a six-over 78 Thursday, is set to miss the cut at the 117th U.S. Open after shooting a one-under 71 during second-round play at Erin Hills in Erin, Wisconsin, on Friday. 

That figure left McIlroy at five over for the championship and well off the pace set by Rickie Fowler and Paul Casey:  

The 28-year-old has now missed back-to-back cuts at the U.S. Open and is a combined seven over at his last two starts following a seventh-place finish at the Masters. 

Golf Digest's Brian Wacker and Golf Channel's Justin Ray broke down McIlroy's woes further: 

McIlroy started his day on the 10th tee, and he actually flashed improvement on the back nine.

A day after shooting six over on the back, McIlroy rebounded and played it at even-par. However, that didn't cut it on a day when McIlroy needed to make birdies galore in order to make his way inside the cut line. 

Instead, the world No. 2 was limited to one birdie over his first nine holes as he continued to miss makeable putts with chances to bring his score closer to red numbers. 

McIlroy sealed his fate at the turn when he failed to build momentum that could have sparked a late run.

With back-to-back par 5s on Nos. 18 and 1 presenting strong scoring opportunities, McIlroy played that crucial two-hole stretch at one over following a bogey on the first. That dropped shot represented the first of three straight bogeys. 

McIlroy collected himself and played the final six holes at an impressive four under, including a near-ace on No. 9, but it was too little, too late, after he repeatedly squandered quality looks early.  

And as the Desert Sun's Larry Bohannan noted, it shouldn't have come as surprise McIlroy struggled at what's annually the hardest major after he missed extended time earlier in the year due to a rib injury: 

If there's a silver lining for McIlroy, it's that several other highly-ranked talents—including playing partner and world No. 3 Jason Day (+10)—failed to crack the Erin Hills code over the tournament's first 36 holes. 

Ray shed light on the historical significance of those missteps: 

The Northern Irishman will now attempt to hone his game and round into form before the Open Championship in July.  

And if his solo fifth-place finish in 2016 was any indication, the 2014 Open champion should have a shot at breaking through once again when the major scene shifts to Royal Birkdale next month.