Montreal’s rookie camp will open the day before the tournament, followed by their first game September 8 against the Toronto Maple Leafs.
The Canadiens rookies will also play the Ottawa Senators September 9.
McEwan, who has gone undrafted by an NHL team, is entering his fourth OHL season.
Last year McEwan scored 19 goals and 39 points in 58 regular season games. He scored 25 goals the year prior.
This is McEwan’s second time skating with the Canadiens, as he attended the team’s Development Camp in July. Last summer, he skated at the Pittsburgh Penguins Development Camp, and earned a spot with the Penguins at a different NHL preseason rookie tournament.
McEwan is entering his final season of OHL eligibility.