Coetzee made his international debut for South Africa on 6 July 2002 in a match against Samoa at Loftus Versfeld in Pretoria, which the Springboks won 60-18.
In June 2003 he played in two tests against the Scottish in South Africa, which were both won by the Springboks. He subsequently played in the following test against Argentina in Port Elizabeth in which he scored a try.