Jack Oosterlaak

Jack Oosterlaak ("Justus Kinloch Ayres Oosterlaak;" 15 January 1896, in Wellington – 5 June 1968), was a South African athlete who competed mainly in the 400 metres.
He competed for South Africa in the 1920 Summer Olympics held in Antwerp, Belgium in the 4 x 400 metre relay where he won the Silver medal with his teammates Harry Davel, Clarence Oldfield and Bevil Rudd.