McGrane had birdies on the final two holes for a 205 total, three strokes ahead of Michael Lorenzo-Vera (72) and former Augusta State player Oliver Wilson (70). Lorenzo-Vera led after each of the first two rounds on the CBD International course.
Scott Strange had the best round of the day, shooting 6-under 66 to put him five shots behind McGrane in the $2.2 million event jointly sanctioned by the European and Asian tours.
Defending champion Markus Brier (72) is seven shots off the pace.
McGrane had seven birdies and three bogeys. He is seeking his first victory after a runner-up finish at the Indian Masters in February.
Wilson had five birdies and three bogeys.
Lorenzo-Vera, whose two birdies were offset by two bogeys, is seeking his first title in his first year on tour.
LPGA TOUR: In Reunion, Fla., Lorena Ochoa left her fellow golfers in an all-too-familiar position: trying to make up ground on the Mexican star.
Ochoa shot 7-under 65 in the third round of the Ginn Open, moved to 16 under par and took a one-shot lead over Yani Tseng. She also edged closer to her fourth consecutive victory.
Carin Koch kept pace with Ochoa most of the day before a bogey-double bogey finish dropped her six shots back.
CHAMPIONS TOUR: In Lutz, Fla., Mark Wiebe followed his opening 66 with 65 to take a three-stroke lead in the Outback Steakhouse Pro-Am.
Wiebe, coming off a victory two weeks ago in the Cap Cana Championship in the Dominican Republic, reached 11 under to tie the event 36-hole record held by Bruce Fleisher (2000 and 2002).
Defending champion Tom Watson (71) and Scott Hoch (67) were 8 under, and Tom Jenkins (66) and Mike Reid (68) followed at 6 under.
NATIONWIDE TOUR: In Athens, Ga., former Georgia standout Brendon Todd and Greg Owen are tied at 10-under 216 heading into today's final round of the Athens Regional Foundation Classic.
Todd shot 70 in the third round Saturday at Jennings Mill Country Club. Owen had 69. Augusta's Scott Parel (69) is tied for 11th and five shots back.