Many may not have known how to pronounce his name at the beginning of the week, but they do now. Louis Oosthuizen won the 2010 British Open by seven strokes for his first major championship. Oosthuizen’s seven-stroke victory was the biggest margin in the British Open since Tiger Woods defeated Ernie Els and Thomas Bjorn by eight here at St. Andrews in 2000. Lee Westwood was the closest competitor on this day, finishing at 9 under. Paul Casey, who played with Oosthuizen, finished in a tie for third at 8 under. Oosthuizen held onto his third-round lead with steady play on Sunday, which included an eagle on the par-4 ninth, as he carded a 71 to finish 16 under for the week.