Clemson senior Cody Proveaux

Today's opening round scores reflect the depth of the field.

Many of them came "this close" to making the U.S. Open field in sectional qualifying last Monday. One of them — Claudio Correa of Chile — is coming off a Sunday win at the Mexican International Amateur. He kept the heat on with a round of 66 today.

At the end of a long, overcast day in Pennsylvania, only one name is at the top of the leaderboard — Cody Proveaux of Leesville, South Carolina. One of the last players on the course, Proveaux birdied the 16th hole to emerge from a four-way tie at 5-under and get in the clubhouse at 6-under 64.

The former AJGA standout is no stranger to low numbers. In March, he tied a 30-year-old Clemson record for the lowest 18-hole round in a tournament when he fired 63 at the Palmetto Intercollegiate.

GIVING CHASE

Chasing Proveaux are four players at 65, with a full 37 players shooting 1-under 69 or better. Evidently, the moist greens were allowing the players to throw darts today. And 6,868 yards isn't a long layout by today's standards.

2014 Dixie Amateur champion Brandon Matthews of Dupont, Pa. parred his first seven holes before birdies at Nos. 8 and 9 got him to 2-under, and he made no mistakes on the back nine, recording three birdies and six pars to close out with a 32 and round of 5-under 65.

Two Georgians fired the same number.

Scott Wolfe of St. Simons Island had a pair of bogeys, but his seven birdies did away with those and then some. Finishing birdie-birdie closed Wolfe out with a red-hot back nine of 4-under 31.

Robert Mize of Columbus had the most amazing start you could ever hope for in a 72-hole event. Mize, the son of 1987 Masters champ Larry Mize, holed his second shot on the 439-yard par 4 1st hole, showing up on the Golfstat online scorecard in bright yellow, lest anyone miss it. (We certainly didn't.) After that it was three more birdies on the front nine for an amazing 5-under 30. Mize cooled off a bit on the back nine, posting 35 for his 65.

Imagine if the two guys from Georgia were playing best-ball. Their score would be 59.

One of the last players on the course, Chase Koepka (brother of Brooks Koepka from the PGA Tour) birdied the 18th to grab a share of second at 65.

We'll be following the Sunnehanna Amateur all week.