Simplify the following text for a Grade 11 native English-speaking person.
Original: The Tri Nations is an international rugby union competition that is contested annually by Australia , New Zealand and South Africa . The competition is organized by SANZAR , a consortium formed by the three countries ' rugby governing bodies â `` the Australian Rugby Union , the New Zealand Rugby Union and the South African Rugby Union .
Simplified: The Tri-Nations ( rugby union ) is an annual rugby competition between New Zealand , Australia and South Africa .