Lodewicus Theodorus "Louis" Oosthuizen is a South African professional golfer who won the 2010 Open Championship. He has finished runner-up in all four major championships: the 2012 Masters Tournament, the 2015 and 2021 U.S. Open, the 2015 Open Championship, and the PGA Championship in 2017 and 2021. His highest placing on the Official World Golf Ranking is fourth, which he reached in January 2013.

The Open Championship, often referred to as The Open or the British Open, is the oldest golf tournament in the world, and one of the most prestigious. Founded in 1860, it was originally held annually at Prestwick Golf Club in Scotland. Later the venue rotated between a select group of coastal links golf courses in the United Kingdom. It is organised by The R&A.