DeFrancesco, the 43-year-old professional of Woodholme Country Club, shot a 7-under-par 65 on Thursday to better the standing record of 67 held by three others.
Not far behind DeFrancesco are Bruce Zabriski, the 97 champion of this event, and John Graham of Idaho Falls, Id. They each went around Crosswater in 66 on Thursday.
James Blair and Tim Dunlavey are a shot further back at minus-five.
DeFrancescos round was one of beauty on the first day, as he posted eight birdies against just a single bogey.
He might be crediting the greenskeeper for his play.
The greens are rolling just perfect, he claimed. And, I had the speed nicely and I got the line, and the ball was going in. I made four straight birdies (13 though 16), and I made a real nice 25-footer on nine.
Following Fridays second round of play, the field of 156 will be trimmed to the low-70s and ties, with the top-25 finishers following Sundays 72nd hole being invited to this years PGA Championship at the Atlanta Athletic Club.
There are 39 states represented in this years edition of the Club Professionals Championship. The Crosswater Club ' at 7,470 yards ' is the longest track the event has ever been contested upon.
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