Nathan turned professional in 1998 and gained his Australasian Tour card in his first season (1998/1999). He made five of ten cuts that year and did well enough to retain his playing privileges although like all in his situation his next task was to find a place to play for the remainder of the year. He decided to try his luck on the Canadian Tour. “There was nowhere else to play really. While the money was not great it was a Tour on which I could develop my game and I enjoyed my time there.”

Nathan played the Canadian Tour in 1999, 2000 and 2001 while returning to Australia each summer. In 2000 he won the Benefit Partners NRCS Classic on the Canadian Tour before returning to Australia for the Australasian Tour where his career was about to take a major leap forward.

 
At the Ericsson Masters at Huntingdale in Melbourne, Nathan holed in one at the 12th hole in the final round and collected a jackpot prize of A$500,000. It gave him the financial boost he needed to fund his golf for the next couple of years and the opportunity to purchase an apartment in Toronto on the shores of Lake Macquarie near his hometown of Newcastle. It also helped him into second place in that event behind Colin Montgomerie.
 
Boosted by the security the windfall had given him he would finish second the following week to Peter Lonard at the ANZ Championship. He finished in 6th place on the money list and headed back to Canada to play there again in 2001.

At the end of 2001 Nathan attempted the USPGA Tour School and advanced to the final stage before finishing 146th. While missing his USPGA Tour card, he had gained limited status on the Nationwide Tour where he would play in 2002. His first season was a struggle eventually finishing with only US$26,000 for his efforts.


Back in Australia at the end of 2002, Nathan’s best finish was when 3rd at the 2003 New Zealand Open although he earned a bigger cheque when 11th at the Johnnie Walker Classic in Perth.
A decision to stay at home in 2003 and play Von Nida Tour events and then the Australasian Tour late in the season seemed to be bearing fruit when he reeled off three consecutive top five finishes in Von Nida Tour events late in the season in between USPGA Tour School commitments. He again made it to the final of the US School in 2003 and although missing out on his card once again, he did gain non-exempt status on the Nationwide Tour where he headed in 2004.

The improvement in his game was highlighted by a much better season on the Nationwide Tour in 2004 with a runner up finish at the Henrico County Open in Virginia coming after a last round of 64. Several further good finishes including two top tens saw him arrive at the Tour Championship needing to win to gain one of the twenty cards on offer to the USPGA Tour.


Heading into the final round at that event in Alabama, Nathan was one behind the leaders Nick Watney and Justin Bolli. His last round saw of 72 him finish 5th and he was destined for the Nationwide Tour again in 2005.


He returned to Australia and in his first Nationwide Tour event in 2005 he finished runner up at the Jacobs’ Creek Open in Adelaide to Steve Bowditch and he was well on the way to what would become a breakthrough year. After finishing third at the Boise Open in September he had secured his card and although he was not able to strengthen his status in the final few events he was on his way to the PGA Tour in 2006.


On his return to Australia he finished third at the Australian PGA Championship but now his focus was on his debut as a cardholder on the USPGA Tour in 2006.