"I don't know what's going on," said Doughty, who has four goals in three Olympic games after scoring just eight times in 59 NHL games this season. "I don't score like this in L.A. at all. A lot of it is just my teammates. They're doing a great job getting me the puck."
Canada closed the preliminary round of the tournament with a win that would've been more helpful had it happened in regulation, when a victory would have made them the top-seeded team in the quarterfinals.
Instead, they'll be ranked No. 3 among the final eight teams.
For the Canada to repeat as gold medalists, they might have to beat standout goalie Jonas Hiller and the Swiss in the quarterfinals and the surging Americans in the semifinals just to play for the title next Sunday.
"You've got to beat the best," said Canadian coach Mike Babcock. "We came here to be tested. To win an Olympic gold medal, you should have to battle incredibly hard to make that happen. Whoever you get, you get."
Sweden gets the top seed as the only team to win all three of its preliminary-round games in regulation. The U.S. will be seeded second, having won a tiebreaker with the Canadians on goal differential.
The Finns will be seeded fourth in the quarterfinals, which begin Wednesday.
If the fifth-seeded Russians avoid getting upset by 12th-seeded Norway, they will play Finland.
"If we are going to play against Russia, it will be a great challenge for us," Finland coach Erkka Westerlund said. "Good hockey team, also good individual players."
On a team that was expected to be led in scoring by superstar Sidney Crosby, it's Doughty a lesser-known defenseman without an All-Star appearance that's become the go-to scorer.
Doughty won the game midway through the overtime, skating into the left circle and flicking a wrist shot that went across and past Finland goalie Tuukka Rask. He scored to make it 1-0 with a shot from the left circle that didn't seem to be particularly hard and with no one distracting the goaltender's view.
"He makes good decisions," Babcock said. "He's got a heavy body so he can play without the puck and he's really dynamic with the puck."
Tuomo Ruutu scored for the Finns midway through the second period, and Rask finished with 25 saves in an otherwise solid performance that included some difficult stops with his glove and pads.
Canada's Carey Price had to make just 14 saves for the win, and Babcock said he hadn't decided if Price or gold-medal winning goalie Roberto Luongo would start in the quarterfinals.
The Finns might have gotten a break when Canada had a goal waved off because of high-sticking early in the game. With the puck resting on top of the net, Rick Nash whacked at it and the puck ended up going past the goal line.
It was negated by video review because of a rule that an attacking player can't raise his stick above the height of the crossbar prior to the puck entering the net.
"As soon as it was on top of the net, the easy way out was no goal," Babcock said.
Finland is the only nation to win three medals in Olympic hockey since the NHL began letting its players participate in 1998.
Its chances to win a fourth medal in this era took a hit when forward Aleksander Barkov, hurt during Friday's win over Norway, was ruled out for the rest of the Sochi Games with a lower-body injury. Barkov was drafted No. 2 overall in 2013 by the Florida Panthers and the 18-year-old has eight goals and 24 points in 54 games this season, his first in the NHL.