US Open Golf Scores 2012: Rory McIlroy and Most Disappointing Day 2 Performers

The world's best golfers stepped up to the Olympic Club course, and most of them got smacked right back down.

The harsh and unforgiving US Open venue chewed up and spit out many of the sport's brightest stars, as they couldn't conquer the impossibly long course.

Although the vast majority of players struggled in the first two rounds, a few disappointing performances stand out among the crowd. Here are the worst from Friday's Day 2 action.

Rickie Fowler (+8)

After climbing the leaderboard early in Round 1, Fowler had an absolute nightmare over his next 27 holes. He went three-over par for his Thursday back-nine, and then he completely crumbled on Friday.

He had two birdies on the day, but those were negated by bogeys on 5, 11 and 12, a double-bogey on 8, and the dreaded triple-bogey on 1.

It was an unfortunate turnaround for the 23-year-old Fowler, who had strung together an excellent series of tournaments coming in. With five top-ten finishes and one victory in 2012, this seemed like the perfect time for Fowler to contend for the US Open crown.

Instead, he's nowhere near the top of the leaderboard.

Ryo Ishikawa (+9)

Fowler's miserable play seemed to rub off on Ishikawa (or vice-versa). The promising 20-year-old joined Fowler by imploding on Friday after a remarkably consistent first round.

Thursday, Ishikawa parred 15 of his 18 holes. However, in Round 2 he came apart at the seams, registering five bogeys, two double-bogeys and just one birdie.

He finished eight-over par for the day, ruining any chance he had at contending in the second major of 2012.

Rory McIlroy (+10)

The trials and tribulations of Rory McIlroy continue.

After missing three of his last four cuts coming in, it would have been unrealistic to expect McIlroy to defend his 2011 US Open title. However, I figured he'd at least make the cut.

Instead, he didn't even get close, finishing at 10-over through two rounds. He was actually somewhat decent in round two (three-over par), but his awful performance on Thursday proved to be his downfall.

With all his success, it's easy to forget that McIlroy is just 23 years old. He's currently suffering through a horrible slump, but as long as he gets his head on straight and keeps his confidence up, he will be back contending for majors in due time.