UPDATE (3:30 p.m.) - Both Pan and Phelan birdied the first hole, and have moved into a tie for third at -1, just one shot off the lead.
A pair of amateurs found themselves near the top of the leader board on Thursday afternoon.
Cheng Tsung Pan, a 21-year-old from Taiwan who made the open as a sectional qualifier, was briefly tied for the lead early in the afternoon after birdies on holes 11 and 14. A bogey on the 16th caused him to fall back.
Kevin Phelan, a 22-year-old Floridian and also a sectional qualifier, found himself tied with Pan thanks to a birdie on the 15th hole. Phelan has major experience, however, having played in the 2010 Open at Pebble Beach.
As of 3 p.m. both players had dropped to even-par, but remain just one shot off the lead, now at one-under.
The last time an amateur won the U.S. Open was when Johnny Goodman conquered North Shore Country Club in 1933, 80 years ago.
Here's a look at the other amateurs who have won:
Francis Ouimet - 1913
Jerome Travers - 1915
Chick Evans - 1916.
Bobby Jones - 1923, 1926, 1929, 1930