Vosloo comes from Pietersburg and turned professional in 1997. He was a member of the silver medal winning South African team at the 1999 All-Africa Games. During his career he played on the Challenger and Futures circuits, with his wins including players James Blake and Robin Söderling. He also participated in qualifying at all four Grand Slam events. In 2002 he won two Challenger tournaments and represented the South Africa Davis Cup team in a tie against Yugoslavia in Belgrade. In the Davis Cup tie he played two singles matches, which he both lost in four sets, to Dušan Vemić and Vladimir Pavicevic.