Y.E. Yang is the leader in the clubhouse at the U.S. Open. (Ross Kinnaird/Getty Images)

So who is this guy?

DOB: 1-15-72.

Full name: Yang Yong-eun.

Birthplace: Jeju-do, South Korea.

Resides: Southlake, Tex.

Turned pro: 1996.

PGA Tour wins: 2 (2009 Honda Classic, 2009 PGA Championship).

Career top 10 finishes: 10.

Career top 25 finishes: 25.

Best major finishes: won 2009 PGA Championship (it was the first time Tiger Woods lost a major that he led after 54 holes), tied for eighth at 2010 Masters.

World golf ranking: 45th.

Check out The Post’s U.S. Open coverage, which includes a leader board, hole-by-hole guide, tee times, spectator’s guide, photo gallery and live blog.