Greg Norman, trying for his fourth victory in eight years in the Doral-Ryder Open, and David Duval, trying for his first PGA Tour title, shared the lead at 10-under 134 after 36 holes.
Norman built a 68 in the second round around booming tee shots and a solid putter that rolled in a half dozen putts outside 10 feet.
Playing in his first tournament on the PGA Tour since October, Norman was most impressive with a rebuilt swing that has unleashed the awesome power of his younger days, harnessed in recent years as he sought greater control.
Duval, meanwhile, took a different route to his 66 as he knocked down the flagsticks with pinpoint iron shots and got five of his six birdies on putts from inside 8 feet.
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