Davis and Coletta, who have both finished runner-up at the Asia Pacific Amateur Championship in recent years with Davis also taking medallist honours as part of Australia's World Amateur Team Championship-winning side in 2016, both earned their right to play the McKenzie Tour via qualifying at recent tour schools.
Davis, who was also the Australian Amateur Champion in 2015, finished 4th at his qualifying venue in San Jacinto in California while Coletta, already a winner of a PGA Tour of Australasia event as a professional, finished 4th at his venue in British Columbia.
Both appear likely to earn PGA Tour invites over the next few months but having a tour on which to play while waiting for such invites will be crucial in their development.
Tasmanian Simon Hawkes and South Australian Brad Moules have also qualified following their successful bids in recent weeks.
The MacKenzie Tour-PGA Tour Canada consists of 11 events, each with prize money of US$175,000 although their final event of the season, the Freedom 55 Financial Championship, is worth US$200,000.
The Tour has now become a feeder tour for the Web.com Tour with the leading five players at season's end earning the right to compete on the Web.com Tour in 2018.
The first event gets underway in Vancouver on June 1.
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