Rory McIlroy at US Open 2016: Leaderboard Score, Twitter Reaction from Thursday

Rory McIlroy struggled Thursday in the opening round of the 2016 U.S. Open at Pennsylvania's Oakmont Country Club, shooting four over and sitting well off of the lead.  

Conditions at Oakmont, a typically difficult course, were even more treacherous because of severe rain and wind. The event suspended play because of the weather, which Fox Sports provided a look at:

McIlroy, who entered among the favorites to win the tournament, according to Odds Shark, made it through 13 holes, and he is tied for 38th place. Andrew Landry, at three under, is atop the leaderboard, which is available below:

The Northern Irishman struggled early, as he bogeyed his second and his third holes. He bounced back with a birdie on hole No. 4, but the rest of the day was not his best golf. ESPN.com's Jason Sobel mentioned that McIlroy failed to take advantage of the favorable conditions before the weather became a factor:

McIlroy would not birdie again, and he netted three more bogeys, including two straight again on his last two holes of the day.

This is not an ideal start for the four-time major champion, according to Justin Ray of Golf Channel:

The PGA Tour's Twitter account also noted that McIlroy's start Thursday could become his worst in his last 10 majors:

Heading into the tournament, McIlroy expected the course to be difficult, as he described Oakmont as inspiring "trepidation" in its players, per For The Win's Luke Kerr-Dineen. 

McIlroy went on to emphasize the importance of mental toughness at the U.S. Open.

"It’s going to be quite the mental grind. You expect that coming into a U.S. Open," McIlroy said. "It’s the toughest test in golf, and you know that, and you have to do everything you can to prepare for that and try to do your best.”

Oakmont, with its fast greens and difficult hole locations, does not produce many great scores. The U.S. Open was last held at Oakmont in 2007, where Angel Cabrera won with a score of five over.

McIlroy felt this was a disadvantage, according to the Associated Press (via PGATour.com). 

"The majors I have won have been soft and under par and more suited my style of game," McIlroy said Tuesday.

His start was not promising, but McIlroy still has five holes to play in his first round before teeing off again on Friday. He has the time and the ability to climb up the leaderboard, so do not count him out just yet.