Gamez and Leonard carded 5-under 67s and Trahan shot a 68. Gamez birdied his final two holes to seize the lead.
Boo Weekley was in fourth place at 15-under 201 after shooting a 10-under-par 62.
The five-round tournament is being played on four golf courses for the first four rounds. The final round will be played on one of them, the Classic Course.