Connor Bedard scored twice in his world championship debut, and Canada overcame a surprise early deficit to open its title defence at the world hockey championship with a 4-2 win over newcomer Britain on Saturday.

The 18-year-old Bedard, coming off a great rookie NHL season with the Chicago Blackhawks, scored twice in a four-minute span of the second period to put the Group A game in Prague out of reach.

“It was a good first game, but we want to keep improving and be on a steady incline of progress throughout the tournament, and we are looking forward to continuing to play games here," Bedard said.

Canada had to rally from a goal down despite outshooting Britain 12-3 in the opening period and 34-15 overall.

“(Britain) was really committed and blocked a lot of shots," Canada head coach André Tourigny said. "They work really hard, and in this tournament it can be hard to generate offence. That is why any team can win games here. Tomorrow we need to continue to get better, because this tournament is all about which team can improve the most.”

Liam Kirk put Britain a 1-0 ahead on a power play eight minutes into the game, but the lead lasted just 30 seconds as Michael Bunting found the back of the net from the point to tie it 1-1.

"I had some time and space, and I knew I could get a good shot off," Bunting said. "I saw (Nick) Paul standing in front of the net, and he is a big guy, but it kind of went right by him and I was happy to see it go in."

Brandon Hagel put the defending champions ahead 5:45 into the second period with a shot high into the roof of the net.

Then it was Bedard's turn.

The teenager beat goaltender Jackson Whistle (30 saves) midway through the frame for his first goal at the senior worlds, scooping up a rebound to reward Canada for sustained pressure in Britain's end.

He made it 4-1 minutes later after Nick Paul fed him with a perfect pass.

Ben O’Connor scored in the third period for Britain when he beat Canada goaltender Joel Hofer, who made 13 saves.

Bedard is a finalist for this year's Calder Trophy as NHL rookie of the year after putting up a team- and rookie-leading 61 points (22 goals, 39 assists) with Chicago despite missing 14 games with a broken jaw.

Canada next plays Denmark on Sunday. Denmark opened with a 5-1 win over Austria behind two goals and an assist from forward Joachim Blichfeld.

"We know Denmark is a good team and they are going to play hard tomorrow, so we need to be ready for that," Bedard said.

Host Czechia was scheduled to meet Norway later in Group A action.

In Group B in the city of Ostrava, Kazakhstan defeated France 3-1 in their opening game.

Another newcomer in the top division, Poland, took last year's bronze medallist Latvia to overtime before falling 5-4. Latvia captain and former Ottawa Senator Kaspars Daugavins had two goals, including the winner, and an assist.

The United States hopes to recover from an opening 5-2 loss to Sweden in a Group B game against Germany later Saturday.

With files from The Canadian Press