By Chris Dunham, PGATOUR.COM ST. SIMONS ISLAND, Ga. – Billy Horschel’s 36-hole lead got him through 51 holes before a double bogey dropped him one back. Horschel heads to Sunday at the McGladrey Classic one shot behind former SEC rival and fellow 2010 q-school graduate Michael Thompson, with whom he shared the final pairing Saturday. Horschel went to the par-4 16th tee with a one-shot lead over Thompson, but had a swing he called a “quick swing” off the teebox and pulled a drive left and into the hazard. After taking a drop 238 yards from the pin, Horschel hit his third shot into the fairway, pitched up and two-putted for a costly double bogey that dropped him from one-up to one-down. “I was trying to aim to the right side of that bunker out there and just hit a little bulled out there – the shot I’ve been hitting all week,” Horschel said. “I just got quick from the top, the club got way out over the top and I just hit it left. I knew it when I hit it.” Horschel had opened up a three-shot edge when he birdied his first two holes, but those would be his only two birdies in an even-par 70 that leaves him at 12 under for the second consecutive night. The 36-hole leader stood still on a day where 45 of 70 players in the field were in red numbers and 19 of them were 3 under or better. These groups include Trevor Immelman, who tied the tournament record with a 62 on Saturday. “I saw Trevor shot 8 under and I think a couple other guys shot 5 maybe, but it’s out there,” Horschel said. “It doesn’t matter how the course is playing. The score is out there if you make the putts and I wasn’t too worried. It would have been nice to be 2- or 3- or 4-under, which I should have been, but even par is even par and it could have been worse.” The round had a chance of becoming worse when Horschel’s second shot on the par-4 18th ended up in a beautification area, 34 yards from the pin. With Thompson rooting him whispering "Come on, Billy. Hit it close" to his caddie, the 24-year old blasted it just inside 10 feet, drained the par putt and exhilarated the crowds gathered around the 18th green with a big fist pump. “It was huge to make that par on 18 with Michael being in there about 10 feet from the hole,” Horschel said. “I was only one back of it as it is. I could easily fallen two, possibly three back from the lead. “I’m in a good position and if I just shoot a low number and give myself a chance, who knows what happens?”