Danny Willett bogeyed the par-4 15th but is still atop the leaderboard at nine under overall, with a two-stroke lead over Dustin Johnson, who has yet to tee off.
Zach Johnson bogeyed the same whole to drop back into a third-place tie at six under overall. He's shooting even par through t 16 holes.
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6:20 a.m.: English golfer Danny Willett is making a move Friday at St. Andrews, scattering four birdies over his first 12 holes of Round 2 at the British Open to drop to 10-under par and claim a three-stroke lead over Dustin Johnson and Zach Johnson.