Wood had an eagle at the par-5, 548-yard 10th hole and seven birdies --six on par 4s -- against one bogey in moving to 15-under 201 after 54 holes.
Wood had five birdies in his first eight holes Friday then had an 8-foot putt for his eagle at No. 10. He had a bogey at the 12th but pulled clear with birdies at Nos. 14 and 16.
Sergio Garcia, one of the four second-round co-leaders, suffered two late bogeys in a 2-under 70 and slipped into a tie for fifth with Branden Grace (67).
The other co-leaders had worse rounds Friday with Marcus Fraser, despite three consecutive birdies in one stretch, shooting 1-under 71. He is tied for seventh. Martin Kaymer, with two birdies and two bogeys Friday, is among those tied for 11th, six strokes behind Wood.
Ricardo Santos, who led after the first round and was tied after Thursday's play, had two double bogeys and four bogeys in a 4-over 76 and dropped into a tie for 38th at 5-under for the tournament.
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