A win in this game would secure the Scots a place in the Barclays Churchill Cup final at the Commonwealth Stadium in Edmonton against the winner of the other pool which comprises the USA, Ireland A and the New Zealand Maori.
Looking forward to the Canada clash, Bates said: "This game will be a huge test for us because it will ultimately determine whether we go home as Churchill Cup finalists or not.
"The win over England confirmed what this team is capable of and we are continuing to develop that positive mentality in our preparation for this game."
In the pack, Edinburgh Gunners duo Alasdair Dickinson and Andrew Kelly come in whilst Craig Hamilton moves to the number 5 shirt to make way for Andy Hall who comes in at 4.
The pack sports an entirely fresh back-row as Reivers pair Andy Miller and Scott Gray are handed starting berths alongside Leeds Tykes No 8 Jon Dunbar.
The only changes in the back division see left wing Rory Lamont rested in place of the top try-scoring Scot in this seasons Celtic League Nikki Walker. Edinburgh young gun Nick De Luca is also introduced alongside the fierce Glasgow Warrior Graeme Morrison.
Scotland A's game against Canada will be broadcast live on Sky Sports 1 from 11pm on Wednesday 7 June.
Scotland A team:15 Calum MacRae (Border Reivers); 14 Simon Danielli (Border Reivers, 13 Graeme Morrison (Glasgow Warriors), 12 Nick De Luca (Edinburgh Gunners), 11 Nikki Walker (Border Reivers); 10 Phil Godman (Edinburgh Gunners), 9 Rory Lawson (Edinburgh Gunners) CAPTAIN; 1 Alasdair Dickinson (Edinburgh Gunners), 2 Andrew Kelly (Edinburgh Gunners), 3 Colin Noon (Biarritz); 4 Andy Hall (Newport-Gwent Dragons), 5 Craig Hamilton (Glasgow Warriors); 6 Scott Gray (Border Reivers), 7 Andy Miller (Border Reivers), 8 Jon Dunbar (Leeds Tykes)
Substitutes:16 Fergus Thomson (Glasgow Warriors), 17 Allan Jacobsen (Edinburgh Gunners), 18 Mark Rennie (Lyon), 19 Ross Beattie (Northampton Saints), 20 Alasdair Strokosch (Edinburgh Gunners), 21 Colin Gregor (Glasgow Warriors), 22 Rory Lamont (Glasgow Warriors)
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