The Asia-Pacific Amateur champion will begin life as a professional in the WA Open at Joondalup Country Club from Thursday.

It means he won't be one of the 10 Australian amateurs at Royal Melbourne later this month when the course welcomes back the tournament Crowe won in Thailand last year.

Victory there afforded the now 21-year-old entry into the Masters and Open Championship last year, the Sydney product the third Australian to claim the Asia-Pacific title after Curtis Luck (2016) and Antonio Murdaca (2014).

The reigning NSW Open champion has PGA Tour of Australasia exemption and, with Order of Merit spoils in mind, wants to play a full domestic season.

"I was quite tempted," Crowe said of the prospect of remaining amateur to defend his title.

"But I felt like I was ready to go.

"The past year's been absolutely amazing.

"I learned a lot about myself, my game, and taking information from all the top players in the world was really, really awesome

"I don't think I've ever been that nervous in (the Masters and the Open) ... but I felt comfortable out there which was a big sign for me to make that next move."

Murdaca won when Royal Melbourne last hosted the tournament and Crowe thinks the home-soil advantage will be tremendous on a firm, sandbelt layout he rates among the best in the world.

"I'm very optimistic," he said at the prospect of an Australian win, before being asked to share some advice.

"Try not to think too much about the two majors," he said.

Lukas Michel was greenside when Crowe won last year and will contest his fourth Championship from October 26-29.

Michel won an Augusta berth in 2020 with a U.S Mid-Amateur victory and knows Royal Melbourne well.

"I caddied there through university ... it's going to play firm," he said.

"We were all there on the last green pulling for him (Crowe). Hopefully one of us can do it again.

"I don't think I've ever been that nervous in (the Masters and the Open) ... but I felt comfortable out there which was a big sign for me to make that next move." – Harrison Crowe.

"I played Augusta in a COVID year, so the biggest carrot dangling is to get back there and get a year with crowds and family."

The Championship will be played on 12 holes from the Dr Alister MacKenzie designed west course, and six from the east.

PGA Tour pro Lucas Herbert was in the field when the event was last held at the course.

"The fact you ask Harrison how tough it was to not play this event and (instead) turn professional speaks volumes," he said.

Herbert said a five-hole stretch between the 3rd and 7th hole on the west course was "as good as it gets in world golf", crediting the firmness, lay-out and varying winds for its difficulty.