Van Zyl represented the Blue Bulls as early as primary school level, appearing at the Under-13 Craven Week competition in 2008. In July 2013, he also played for them at the premier South African high school rugby competition, the Under-18 Craven Week held in Polokwane. He made three appearances and scored two tries in a personal haul of 25 points.[2]
Van Zyl joined the Blue Bulls Academy after finishing high school and represented the Blue Bulls U19 side in the 2014 Under-19 Provincial Championship, starting ten matches and making two substitute appearances as they reached the final of the competition, where they were defeated 26–33 by Western Province U19.[3]
Upon the team's return, Van Zyl was named in the final squad for the 2015 World Rugby Under 20 Championship.[9] He started all three of their matches in Pool B of the competition; a 33–5 win against hosts Italy,[10] a 40–8 win against Samoa[11] and a 46–13 win over Australia[12] to help South Africa finish top of Pool B to qualify for the semi-finals with the best record pool stage of all the teams in the competition. Van Zyl started their semi-final match against England, but could not prevent them losing 20–28 to be eliminated from the competition by England for the second year in succession[13] and also started their third-place play-off match against France, helping South Africa to a 31–18 win to secure third place in the competition.[14]
In June 2015, Van Zyl extended his contract at the Bulls until October 2017.[19] He was included in the Blue Bulls squad for the 2015 Currie Cup Premier Division and named in the matchday squad for all eleven of their matches in the competition. He made his Currie Cup debut by playing off the bench in their 57–19 victory against the Free State CheetahsinBloemfontein in their opening match of the season.[20] After appearing as a replacement in their next two matches against Griquas[21] and Western Province,[22] he made his first Currie Cup start in their Round Four match against the Free State Cheetahs in Pretoria.[23] He appeared as a replacement in five of their remaining six matches during the regular season of the season, helping the Blue Bulls finish in second position to qualify for the play-offs. He played off the bench in their semi-final match against Western Province, but could not prevent the side from Cape Town winning 23–18[24] to eliminate the Blue Bulls from the competition.
On 23 February 2021, Van Zyl signed for Saracens ahead of the 2021–22 season.[26] He helped Saracens win the Premiership title in 2023, scoring a try in the final as Saracens defeated Sale Sharks.[27]
