2008–2009: Schoolboy rugby

Kotzé was born in Vredendal in the Western Cape, but grew up in Mpumalanga province, where he attended Hoërskool Nelspruit. He was selected to represent the Pumas at the Under-18 Academy Week in 2008,^[2] and at South Africa's premier youth tournament for high schools – the Under-18 Craven Week – in 2009.^[3] He started all three of their matches at the tournament held in East London, scoring one try in their 14–41 defeat to the hosts Border.^[4]

At the conclusion of the Craven Week, he was included in a South Africa Under-18 High Performance squad that played three international matches against their counterparts from France and Namibia during August 2009.^[5][6] He was named on the bench for all three matches; he failed to make an appearance in their 39–3 victory over France in the first match,^[7] but played off the bench in their 93–10 victory over Namibia^[8] and their 39–6 victory over France in their second encounter.^[9]

2010–2012: Western Province and Sharks

After school, Kotzé moved to Cape Town to join the Western Province youth structures. He was a key member of the Western Province U19 squad that participated in the 2010 Under-19 Provincial Championship, appearing in nine of their twelve matches during the regular season, scoring tries in matches against Griffons U19^[10] and Sharks U19^[11] en route to securing top spot in the log to qualify for the title play-offs.^[12] Kotzé came on as a replacement in their semi-final match against Free State U19, a game that finished 36–36 after normal time and 49–49 after extra time, but saw Western Province progress to the final by virtue of scoring more tries in the match.^[13] Kotzé also played off the bench in the final, a 43–32 victory over Blue Bulls U19 to be crowned the 2010 champions.^[14]

He was not used by Western Province in 2011, instead making a single appearance for the Durban-based Sharks U21 team in the 2011 Under-21 Provincial Championship.^[15]

He was included in the Western Province U21 squad for the 2012 Under-21 Provincial Championship, but after making three appearances, he made a mid-season move to the Johannesburg-based Golden Lions outfit.

2012–2013: Golden Lions

Kotzé made seven appearances for Golden Lions U21 in the 2012 Under-21 Provincial Championship after his mid-season switch, scoring a try in their 32–all draw against Free State U21,^[16] However, the team finished in fifth spot, missing out on the play-offs.^[17]

He was included in the Golden Lions' squad for the 2013 Vodacom Cup and he made his first class debut on 5 April 2013, starting in a 19–30 defeat to the Griffons.^[18] That was his only appearance in the competition that the Golden Lions eventually won, beating Kotzé's former side the Pumas in the final.^[19]

2013–2014: Boland Cavaliers

Kotzé was soon on the move again, joining Wellington-based side the Boland Cavaliers for the 2013 Currie Cup First Division competition. After an appearances off the bench against the SWD Eagles to make his debut in the Currie Cup competition,^[20] and a second one against the Border Bulldogs,^[21] he made his first start in a 20–7 victory over the Falcons.^[22] He remained in the starting line-up for the majority of the season, making a total of thirteen appearances in their fourteen matches.^[23] Boland finished the season in fifth place, failing to qualify for the semi-finals.^[23]

He was named in their squad for the 2014 Vodacom Cup, but failed to make any further appearances for the team.^[24]

2014–present: White River / Pumas

He returned to Mpumalanga, where he played amateur club rugby for White River. At the end of 2015, the Pumas invited nine amateur and youth players to train with them and Kotzé was one of three players that were awarded a contract to play for the team during the 2016 Currie Cup qualification series.^[25] He did not feature in any of their first five games, but appeared in all of their remaining nine matches in the competition. His Pumas senior debut came off the bench in a 25–13 victory over the Blue Bulls,^[26] and was also used as a replacement for their next four fixtures. In the final one of those – a 35–13 victory over the Sharks XV – Kotzé scored his first senior try two minutes from the end of the match.^[27] He found himself in the run-on side for their next match against the Eastern Province Kings^[28] and, after two more appearances as a replacement, made his second start for the Pumas against the Griffons, scoring his second senior try to help his team to a 60–17 victory.^[29] The Pumas finished fourth on the log, which was enough to ensure they would progress to the Premier Division of the Currie Cup.^[30]

Kotzé's contract at the Pumas was extended, as he was also named in their squad for the Currie Cup proper,^[31] and he made his debut at that level in their 10–33 defeat to the Sharks, coming on as a replacement in that match,^[32] as well as matches against Griquas^[33] and Boland Cavaliers.^[34]