Marais played for the Boland Cavaliers in youth competitions and was part of the 2009 Vodacom Cup squad, without making a senior appearance.

Although Marais didn't play any games for the Leopards during the 2010 Currie Cup season, he made his first class debut in the Leopards' first relegation play-off match against the SWD Eagles, scoring his first try within a minute of his debut when he came on as a first-half blood replacement and a second try right before the end of the match.

[2] He maintained his try-scoring exploits in the following match, scoring another try in the return leg[3] to help keep the Leopards in the 2011 Currie Cup Premier Division.

[15][16] At the end of 2015, Marais was one of a number of players that joined the Southern Kings prior to their return to Super Rugby for the 2016 season.

[20] Shortly after the 2016 Super Rugby season kicked off, Marais joined the Pretoria-based Bulls on a two-month trial basis.