After a scoreless second period, Flick broke a 1-1 tie at 11:51 of the third to bring the Hershey Centre gathering of 5,429 to its feet. After taking a pass, Flick went wide to beat the Ice defenceman before firing a shot on his forehand past Kootenay goalie Nathan Lieuwen.
Mississauga goaltender J.P. Anderson was solid, stopping 33 shots.
The win was the first of the tournament for Mississauga (1-1) while Kootenay dropped to 0-2. While the Ice still remains in contention to win the Memorial Cup, history certainly isn't on its side.
Only one team has ever rallied from a 0-2 deficit to capture the title, that being the Windsor Spitfires two years ago.
Maxim Kitsyn had the other goal for Mississauga, which finished 0-for-6 on the power play. The Majors were 2-for-7 with the man advantage in their opening 4-3 loss to the Saint John Sea Dogs.
Cody Eakin scored for Kootenay, which responded with a much better effort following a 5-0 defeat Saturday night to the Owen Sound Attack.
The WHL-champion Ice played minus captain Brayden McNabb. He was suspended for one game earlier Sunday for elbowing Owen Sound's Joey Hishon late in the third period Saturday night.
Hishon, a 5-foot-10 Colorado Avalanche prospect, had made his way into the middle of the ice when the 6-foot-4 McNabb, a defenceman, hit him in the head with his elbow. McNabb went down hard to the ice and began bleeding.
McNabb received a five-minute major and game misconduct for the hit. With McNabb out of the lineup, Kootenay went with three assistant captains: Kevin King, Matt Fraser and Steele Boomer.
Eakin scored Kootenay's first goal of the tournament on the power play at 7:55 of the first. Kitsyn erased the advantage, countering just 1:23 later to make it 1-1.
Top spot in the tournament standings will be up for grabs Monday night when Saint John battles Owen Sound. Both clubs won their opening game and the winner will remain the event's lone unbeaten squad.
The Attack hopes to know the status of Hishon for the game. The club's scoring leader during the regular season wasn't on the ice for an optional skate Sunday although he did exercise and some light stretching.