Hayden Paddon held off the challenge of Sebastien Ogier in the final three stages to claim his first WRC victory at the Rally Argentina by 14.3 seconds.
Paddon's previous best had seen him finish second twice in his Hyundai but he finally climbed the top step of the podium on Sunday.
"I almost can't believe it," said Paddon. "I gave that stage absolutely everything!
"I've been preparing for this stage for three weeks. In the past the tight and twisty stuff really didn't suit me.
"I didn't think we had a chance - today I just drove the wheels off. We're going to win a lot more with this car."
Heading into the final day of the rally, Paddon held a 29.8-second lead after seeing former leader Jari-Matti Latvala crash on stage 14.
However, his advantage was slowly cut by three-time champion Ogier on stages 16 and 17, the Frenchman taking a particularly big chunk as he won the latter.
Paddon's advantage was just 2.6secs heading into the final power stage, and he turned on the style to cross the line fastest in 13 minutes and eight seconds, with Ogier back in third.