Callan O'Reilly has won the 2015 BMW Tahiti International Open in one of the most dominant displays in the events 31 year history.

Callan O'ReillyStarting Sunday's final round six shots ahead of New Zealand's Daniel Pearce, O'Reilly held his nerves in the early stages to maintain his lead.

By the ninth hole O'Reilly had extended his lead seven shots with Fraser Wilkin and Edward Stedman the only challengers to rally on the final day.

The final grouping of O'Reilly, Pearce and Andrew Kirkman were faced with sweltering Pacific temperatures reaching the mid 30's by noon.

"I really battled today and probably wasn't as relaxed as I was in the first three days but it's an amazing feeling right now," said the 24-year-old O'Reilly with the victory also marking his first 72 hole win.

"It was amazing weather all week and today was really hot by the time we teed off but the weather is one of the great reasons this event is so popular".

O'Reilly hit the professional scene in style, claiming the victory at the 2013 PGA Tour of Australasia Qualifying School.

Since turning professional, the young gun from Toronto Golf Club on the NSW Central Coast has by his own standards had mixed form with several top results on the PGA Tour of Australasia and several wins on the Choice Hotels PGA Pro-Am Series.

"This is certainly the biggest win of my career to date" said O'Reilly.

"I don't think I have ever played as solid for 72 holes as I did this week and driving the ball as well as I am right now."

"When I hit that great shot into the par-three 17th hole I felt like I was in control and had my nerves in check," he added.

New Zealand's Fraser Wilkin posted the low round of the day with an eight-under-par 64 to finish in outright second.

Pearce came unstuck on the par-four 15th where an errant tee shot into the left trees resulted in a double bogey six and fall out of contention.

Tournament favourite and recent SIFA Samoa Open winner Mitchell A. Brown posted a final round 68 to finish in a tie for fourth place.