Brodt scored the winner when the puck deflected off her midsection and past Canadian goaltender Shannon Szabados at 18:32 of the third period.
“It came pretty fast, somewhere in my chest it hit me,” Brodt said. “I was lucky enough to be standing there and it was awesome.”
The hosts relied on Szabados early as Canada was outshot 25-14 for two periods, yet only trailed 1-0 heading into the third.
“We’ve got to put the puck deep,” Canadian captain Marie-Philip Poulin said. “We kind of created a couple of turnovers at our blue lines.
“We know Szabby is a great goalie. She’s going to stand on her head for us, but we’ve got to help her out.”
Hannah Brandt also scored for the defending champions in the first meeting between Canada and the U.S. since the Americans prevailed 3-2 in a shootout in February’s Olympic final.
Loren Gabel’s first career goal for Canada was bittersweet as it accompanied a loss.
The 20-year-old from Kitchener, Ont., evened the score at 3:30 of the third period in front of approximately 3,500 at the SaskTel Centre.
“Scoring that goal, we got a lot of energy from it,” Gabel said. “We definitely brought it to them in the third, but just couldn’t come out with the win.”
Szabados started her second game in as many days and made 31 saves in the loss.
Alex Rigsby got the nod for the U.S. after Maddie Rooney played the tournament-opener. Rigsby repelled 23 shots for the win.
Canada (1-1) and the U.S. (2-0) cap the preliminary round Friday against Finland and Sweden, respectively.
Finland improved to 1-1 earlier Tuesday with a 3-2 win over Sweden (0-2).
The two countries with the best records after the preliminary round play for gold and the third and fourth seeds for bronze Saturday.
Canadian coach Perry Pearn, a longtime NHL assistant coach, and U.S. counterpart Bob Corkum, a former NHL defenceman, are coaching their respective country’s women’s teams for the first time at the Four Nations.
“I’ve seen enough U.S.-Canada games,” Pearn said. “You know every time you play them, it’s going to be a fine, fine line between winning and losing.
“We talked about having a good first five minutes and we didn’t. Our best period was the third period. We did enough that if we got a break, we might have been able to win the game.”
“At the end, you still have to be a little bit better than we were on the last goal.”
The U.S. started fast outshooting Canada 16-4 in the opening period. Brandt struck at 1:18 scoring on a rebound during a goal-mouth scramble.
“Our philosophy is to have a shooter’s mentality and get many shots on net, and get to the net,” Corkum said. “That seems to be the way goals go in these days at any level. The goalies are just so good.”
Veteran Canadian forward Brianne Jenner did not play a second straight game because of an injury, but Pearn was hopeful she will be in the lineup Friday against the Finns.
The U.S. had a man advantage late in the third period with Canadian defender Halli Krzyzaniak in the box for body checking, but the Canadians survived it with help from Szabados.
The Americans went scoreless on three power-play chances, while the Canadians were 0-for-2.
Trailing 1-0, Canada started the third on the power play because of an Emily Pfalzer tripping penalty to end the second.
After the Americans killed the penalty, Gabel followed up a broken 2-on-1 involving Kristin O’Neill and Jamie Lee Rattray, banging a rebound over Rigsby at 3:30.