The 2004 mid-year rugby union tests (also known as the Summer Internationals in the Northern Hemisphere) refer to international rugby union matches that are played through June, mostly in the Southern Hemisphere.
Four test series was included in the window with Argentina hosting Wales, Australia hosting Scotland, New Zealand hosting England and South Africa hosting Ireland. The Southern Hemisphere greats topped the series, winning all the tests to give the Northern Hemisphere a series white wash - although, the rising nation Argentina, earned a series draw with the Welsh side.
The Barbarians ended their season with a three win-one loss result, following a victories over Scotland and England and a first visit to Portugal victory to go with it. Wales were the only team to defeat the Barbarians on their 2004 tour. The Pacific Islanders rugby team toured the Tri Nations (or the Southern Hemisphere greats) for the first time, losing all three matches.