Canada's chemistry experiment continued into the medal games at the women's world hockey championship, although Sarah Fillier found her scoring touch in Canada's 9-1 quarterfinal win over Japan on Thursday.

Fillier, the tournament's MVP two years ago in Brampton, Ont., scored her first two goals of the championship.

Jennifer Gardiner, who was separated from linemates Marie-Philip Poulin and Laura Stacey for the first time, also scored twice for a tournament-leading five goals.

Defending champion Canada meets last year's bronze medallist Finland and the United States faces host Czechia in Saturday's semifinals. The medal games are Sunday.

Canada opened the tournament with a 5-0 blanking of Finland.

The Canadians played Thursday's fourth game at Budvar Arena with a puck drop at 8:30 p.m. local time after Czechia thumped Switzerland 7-0, the United States blanked Germany 3-0 and the Finns got by Sweden 3-2.

WATCH | Canada thrashes Japan in women's hockey worlds quarterfinal:

Gardiner, Fillier lead Canada to semifinals at women's hockey worlds with dominating win over Japan

Canada defeats Japan 9-1 in the quarterfinals of the women's world hockey championship. Jennifer Gardiner scores twice and leads the tournament with five goals, while Sarah Fillier also notches a pair.

Poulin's assist on Julia Gosling's goal was the 86th point of the captain's career in world championships, which tied Hayley Wickenheiser's Canadian record.

Canada outscored its opposition 17-3 in the preliminary round with the trio of Poulin, Gardiner and Stacey contributing eight of those goals.

Head coach Troy Ryan stirred his forward lines Thursday in search of more balance ahead of the high-stakes final weekend.

Fillier, a centre most of her career, has played wing in her rookie PWHL season with the New York Sirens and also did so in Canada's Pool A games.

Spooner, who didn't dress the previous game and played on other lines to start the tournament, joined Nurse and Fillier while the latter shifted to the middle Thursday.

"A lot of my game is speed, finding the puck with speed, and as a centre, you can do that all through the ice, instead of kind of being stuck on one side of the ice," Fillier said. "I love playing centre, so it's nice to be back there for the game."

Added Ryan: "There's been a little frustration in her game at times, so sometimes you just try to put them back in their natural position. I challenged her a little bit that she needs to have more of an impact on both ends of the rink. She just played with a little bit more attitude and energy."

Daryl Watts was given a look with Poulin and Stacey, while Gardiner shifted to a fourth line with Kristin O'Neill and Emma Maltais. The trio of Brianne Jenner, Blayre Turnbull and Emily Clark stayed intact.

"One of the big things was just trying to find a fourth line that we could rely on generally to take some defensive zone play away from [Poulin] and Fillier and those types of players," Ryan explained.

"I still may juggle a little bit to see who the ideal person is to play with Poulin. We may juggle a bit more in the semifinals.

Clark contributed a goal to the win over Japan, but Canada also benefited from back-end production.

Defender Claire Thompson had a goal and two assists, Ella Shelton and Sophie Jaques each scored and Renata Fast had three assists.

Kristin Campbell stopped five of six shots for her third win, while workhorse Japanese counterpart Miyuu Masuhara repelled 53 shots.

Mei Miura scored Japan's first goal against Canada in nine meetings and briefly drew her team within a goal at the game's midpoint before the Canadians pulled away.

"Give Japan a lot of credit. They blocked a ton of shots today and they made it difficult for us, but as we continue to get our lines rolling, I think that we were able to create a lot more too," said defender Erin Ambrose.

The Japanese were minus one of their stars. Former Ottawa Charge forward Akane Shiga injured her left knee in her team's preliminary-round finale against Germany and was removed from the ice on a stretcher.

Canadian forward Danielle Serdachny, defender Micah Zandee-Hart and goaltender Ann-Renee Desbiens didn't dress for the quarterfinal.

Czech Republic 7, Switzerland 0

Natálie Mlýnková scored a hat trick as the Czech Republic produced a five-goal opening period en route to a 7-0 rout of Switzerland and a fourth straight semifinal appearance.

Mlýnková scored two power-play goals and added another short-handed. Tereza Vanisova and Kristýna Kaltounková each had a goal and two assists, and Daniela Pejšová, and Denisa Křížová also scored for the Czechs, who claimed bronze in two of the previous three years of the championship.

Klara Peslarova stopped 14 shots for her shutout.

Finland 3, Sweden 2

Finland became the first team to reach the semifinals at the women's ice hockey world championship by beating Sweden 3-2 on Thursday in Ceske Budejovice, Czech Republic.

Sweden answered through goals from Ebba Hedqvist and Josefin Bouveng in the second.

Susanna Tapani gave the Finns the lead for good with 8:14 remaining in the frame.

The Swedes have to settle for the fifth-place game on Saturday.

U.S. 3, Germany 0

The United States cruised past Germany 3-0 to reach the semifinals.

Goalie Aerin Frankel shut out the Germans with 12 saves. Germany last scored against the U.S. at the worlds in 2008.

"Today was an important game, we battled and continued to fight," U.S. head coach John Wroblewski said. "Germany is a tough, physical team and we stuck to our game and got the win."

Pannek one-timed a shot from the left circle for her third goal at the tournament 5:36 into the quarterfinal. Eden added the second midway through the opening period from the slot.

Carpenter scored from close range with 1:07 remaining in the second period.

The U.S. has reached the final in all 23 previous worlds and won 10 titles.

Later, the host Czech Republic faces Switzerland while defending champion Canada meets Japan at 2:30  p.m. ET.