Mediate's stellar outing garnered him both the 18- and 36-hole records at The Old Course at Broken Sound Club. He finished the day at 16-under 128, three clear of first-round co-leader Tom Pernice Jr.
Pernice carded a 7-under 65 while Bernhard Langer -- who had a share of the lead after Friday's first round -- registered a 67 to finish alone in third at 11-under 133.
David Frost carded a 65 to take sole possession of fourth at 9-under.
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