Sweden's Alex Noren led the European challenge as America's Ryan Moore produced a remarkable run of scoring to dominate the early stages of the WGC-Cadillac Championship.
Noren missed almost all of the 2014 campaign with tendonitis in both wrists, but currently sits tenth on The Race to Dubai after finishing ninth in Qatar, second in Dubai and 11th in Thailand.
The three-time European Tour winner was four under through 12 holes of Doral Trump National's Blue Monster and third on his own.
But Noren was a whopping four shots behind leader Moore, who raced to the turn in 31 and added a hat-trick of birdies from the tenth to be eight under.
Another of the home contingent, former US Ryder Cup star JB Holmes, was second on seven under having eagled the 12th after a drive of 376 yards.
Patrick Reed had made a remarkable start to his title defence when he carded an opening hat-trick of birdies then holed a 20 footer on the 15th to go to four under, but driving into a bunker on the 18th cost him a bogey.
Reed was joined on three under by compatriot Ryan Palmer and France's Alex Levy.
Holmes joined Moore on eight under with a birdie at the third, while Levy set the clubhouse target on four under after an opening 68.
"It was a very good round," said Levy, who is making his tournament debut this week. "In very tough conditions I played really good golf. I hit some good shots in good positions; that was the key today."
