ST. ANDREWS, Scotland, July 17 (UPI) -- South African Louis Oosthuizen fired a 3-under-par 69 Saturday, keeping a firm grip on the top spot of the British Open leaderboard after three rounds.
Oosthuizen, who led by five shots after the weather-delayed second round, ended the day on St. Andrews' Old Course at 15-under 201, four strokes ahead of Paul Casey, who carded a 5-under 67.
Oosthuizen's only title of any kind came this year on the European Tour at the Open de Andalucia in Spain. He also led after three rounds of the Hassan II Golf Trophy in Morocco a week earlier, but Rhys Davies bypassed him in the final round.
Martin Kaymer (68) ended the third round three strokes further back at minus-8. Henrik Stenson (67), Alejandro Canizares (71) and Lee Westwood (71) are knotted in fourth place at 7-under 209.
Two-time British Open winner Tiger Woods continued to struggle in his comeback from a self-imposed exile in the wake of a sex scandal, shooting a 1-over 73, good for an 18th-place tie at minus-3.
Phil Mickelson, the world's No. 2 golfer, carded a 2-under 70, putting him in a 26th-place tie, while defending champion Stewart Cink (71) was tied for 38th at minus-1.
