Russell Knox dropped four shots in the final two holes of his Masters debut to card a seven-over par 79.
The 30-year-old from Inverness was one over at the turn, but a five at the par-three 12th and a triple-bogey on the 18th blighted his first round.
The veteran Sandy Lyle, whose advice on Augusta Knox had sought prior to his first round, shot a four-over par 76.
Three over after eight holes, the 58-year-old 1988 Masters winner knocked in nine pars before a bogey at the last.
The winner of six PGA Tour titles is 10 shots behind the clubhouse leader, reigning champion Jordan Spieth.
Florida-based Knox also dropped shots at the par four 5th, 11th and 17th holes, but did register a birdie at the 510-yard par-five 13th.
He will tee off for his second round on Friday with New Zealand’s Danny Lee and America’s Smylie Kaufman at 14:26 BST.
Lyle, Austria’s Bernd Wiesberger and the American Vaughn Taylor begin their second round at 16:49 BST.
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