(Reuters) - England’s Andy Sullivan carded a second-round 66 on Thursday to lead by three shots at the halfway stage of the Golf in Dubai Championship at the Jumeirah Golf Estates. Overnight leader Sullivan shot five birdies and an eagle on the seventh hole of the Fire Course after a blip on the third that resulted in his first bogey. He went 17-under for the tournament. The English Championship winner’s compatriots Matt Wallace and Ross Fisher were both three strokes behind in second place after registering identical rounds of 67. “It was basically just to stay patient and give ourselves as many chances as possible,” Sullivan said. “It’s hard, as much as I had to work hard at staying patient today, when I was three under through nine it didn’t feel as good as yesterday. “You know you’re still on the right track. I knew I was swinging it well and knew if I kept giving myself opportunities I could make a few coming in. If you told me I’d shoot 61-66, I would have snapped your hand off. “It sounds cliche but I just stuck to my process of what I could do. It was the only thing I can control out there and it’s been working. I feel like I have the golf ball in some sort of control at the moment.” ADVERTISEMENT Sullivan, who set a course record on Wednesday, went close to matching Ernie Els’ 36-hole European Tour scoring mark of 18-under-par at the 2004 Heineken Classic, but he missed a birdie putt on the final hole. Frenchman Antoine Rozner was tied-fourth alongside Germany’s Max Schmitt and Scotland’s Craig Howe on 12-under. Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Toby Davis