 Mark Sanders made his first-class debut in February 1999, playing for KwaZulu-Natal B against Northerns B in a UCB Bowl match, scoring 35 in KwaZulu-Natal's only innings.In the same season, he also played another UCB Bowl match against Western Province B, scoring 88 runs.He made his Supersport Series debut for the main KwaZulu-Natal team against Griqualand West.