Shane Lowry and Paul Dunne finished in a tie for tenth at the World Cup of Golf while victory went to Belgium's Thomas Pieters and Thomas Detry.
The Irish team of Lowry and Dunne carded a final round of 71 to end the tournament of 12-under.
Belgium won the $7 million tournament by three strokes in Melbourne on Sunday to secure their country's first title triumph in the team event.
Overnight leaders by five strokes, the young pair survived a late wobble in the final round foursomes at Metropolitan Golf Club, with a bogey on the 15th trimming their lead to two shots over Australia's Marc Leishman and Cameron Smith.
However, they rebounded with a birdie on the 16th, which proved enough to keep the Australians at bay and give Pieters and Detry their biggest tournament win at the 28-nation event.
The Belgian duo's final round four-under 68 left them with a 23-under total of 265, three clear of joint runners-up Australia (65) and Mexico (66).
