At the start of 2013, Beerwinkel made two substitute appearances for a side which won the 2013 Varsity Cup. He was then selected for the South Africa Under-20 that attempted to retain their IRB Junior World Championship title in the 2013 edition held in France. He scored South Africa's first points in the competition, getting a try after just 5 minutes in their first Pool A match against the United States, helping them to a 97–0 victory. He also started their next match, a 31–24 victory over England, and helped South Africa finish the pool stages with a perfect record, playing off the bench in their 26–19 victory against hosts France in their final match of the pool stages. He started their semi-final match against Wales, but couldn't prevent his side slipping to a 17–18 defeat. He was named on the bench for their final match, the third-place play-off against New Zealand, but didn't feature in the 41–34 victory as South Africa secure third spot in the competition.