"It was just an off-day," he said Thursday.
On Friday, the 21-year-old Texan was already returning to form and then some, shooting 7-under through his first 14 holes in the second round at South Carolina's Harbour Town Golf Links.
That put him at 4-under and represented a significant improvement over the 74 he shot on Thursday. Spieth was coming off a whirlwind media tour at the beginning of the week, with stops at numerous television studios where he talked about his win at Augusta National Golf Club.
"My legs are a little tired, but all in all that happens," he said after Thursday's round, noting that Matt Kuchar "is older than me ... and he kicked my butt today, so I've got some work to do."
Kuchar held the lead at 8-under through his first 14 holes. Louis Oosthuizen and Morgan Hoffmann stood in second at 6-under.
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