"I said 'This result means nothing. It absolutely means nothing until we play that final game,'" he said. "And when we beat them in Glasgow, and we beat them 40-0 and it was convincing, I said to the players the same. I said 'This result means absolutely nothing. It's all about winning a one-off game in North Carolina.'"
Barring an upset of immense proportions, that showdown will come Sunday when Canada and U.S are expected to face off in the final of North America Caribbean Rugby Association (NACRA) Sevens Championships in Cary. N.C.
The winner goes to the 2016 Olympics. The loser will have one last chance to get to Rio de Janeiro via a world repechage tournament next year.
The U.S. men finished sixth in the World Series while the Canadians were ninth, with the Americans winning four out of their five meetings.
"Previous results mean nothing," Middleton repeated. "It's just about that 20 minutes (Sunday)."
Still the Canadian coach knows the challenge this weekend is sizable.
"We are the underdogs coming into this," he said. "There's no question about that."
Both teams will have to handle extreme heat. The forecast calls for a high of 34 degrees Celsius Sunday, feeling like 38.
Canada finished the season strongly, reaching the Cup quarter-finals in four of the last five events. The U.S. won in London, the final stop of the World Series circuit.
Middleton points to the consistency in the American selection this season, with their nine main players available for every tournament bar one. Canada, in contrast, has been hit hard by injuries in Middleton's first year at the helm.
And the Americans boast sizzling speed in Perry Baker and Carlin Isles, with ample strike support from Madison Hughes, Zach Test and Maka Unufe.
But Middleton has been able to name a strong roster, augmented by overseas pros Tyler Ardron, Jeff Hassler, Taylor Paris and Connor Braid.
Ardron, a back-row forward who is captain of the national 15-man team, and winger Hassler both play for Welsh club side the Ospreys. Paris, a speedy winger, recently helped Agen win promotion to France's elite Top 14.
Braid, a back who plays for the Glasgow Warriors, was part of Middleton's squad in London as an emergency injury replacement.
Phil Mack, an influential member of the squad, returns from a knee injury.
The Canadian men have been placed in a pool with the Bahamas, Cayman Islands, Guyana and Trinidad and Tobago. The other group at features the U.S., Barbados, Jamaica, Mexico and St. Vincent.
Middleton will look to use all his squad in the early going while still trying to build team momentum going into the final.
"It's an unusual one in terms of how we approach the tournament. It's very much framing a single game without taking your eye off the fact that you've still go to make your way to that big collision. It's a balancing act."
He says 99 per cent of his team preparation has been around the Americans.
Host Brazil and Fiji, South Africa, New Zealand and England have already qualified for the Olympics by virtue of finishing in the top four of the Sevens World Series.
The other seven Olympic men's teams will come from six regional tournaments plus the repechage competition. Argentina has already qualified via the regional route.
On the women's side, Canada has already qualified for Rio by virtue of its second-place finish in the Women's Sevens Series.
The U.S., which was fifth in the standings, is expected to roll through the NACRA women's field which also includes the Bahamas, Barbados, Cayman Islands, Guyana, Jamaica, Mexico and Trinidad and Tobago.
John Moonlight (capt.), Conor Trainor, Adam Zaruba, Phil Mack, Harry Jones, Ciaran Hearn, Sean Duke, Justin Douglas, Tyler Ardron, Mike Fualiefau, Connor Braid, Nate Hirayama, Jeff Hassler, Taylor Paris.
Coach: Liam Middleton
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