Aldrich Potgieter had the lead going into the final round of the Mexico Open, minus the cushion he enjoyed after a sloppy finish Saturday that made him settle for a 4-under 67 and a one-shot advantage over Brian Campbell at Vidanta Vallarta. Potgieter, the 20-year-old power player from South Africa, started with a four-shot lead and held off one challenge early from Stephan Jaeger, who closed within one shot after six holes. The next challenge came from Campbell, who at times was 50 yards shorter off the tee than Potgieter but made up for it with his putter, including a 60-foot birdie on the par-3 ninth.