Theophilus “Doctor” Khumalo (born 26 June 1967 in Soweto), also known as "16 valve", is a retired South African soccer player. He is best known for being a star midfielder for Kaizer Chiefs as well as the South African national team.
Having started playing soccer in 1984 with Swallows Reserves, Khumalo then went to Kaizer Chiefs, where he initially played for the junior team. His father, Eliakim "Pro" Khumalo, a renowned player of the 1970s and early 1980s, served as his mentor. Khumalo was promoted to the senior team by coach Ted Dumitru the following year, when he started a game against arch rivals Orlando Pirates.
Khumalo went on to become a star player for Kaizer Chiefs and did not play for any other South African soccer club, only leaving them for short overseas playing periods – he signed with FIFA agent Marcelo Houseman who first took him to Argentinian club Ferro Carril Oeste for six months in 1995, while in 1996 and 1997 he played for the Columbus Crew of Major League Soccer.