Complex sentence: Van der Walt earned his second win of 2013 at the Nelson Mandela Championship and was named the winner of the Sunshine Tour's Order of Merit, which also earned him entry into the 2014 Open Championship, his first major.
Split into simpler sentences: Van der Walt earned his second win of 2013 at the Nelson Mandela Championship. The honour also earned him entry into the 2014 Open Championship, his first major.