The 2022 Paralympic Winter Games will run from March 4-13, and each day, NBCOlympics.com will recap the biggest stories that happened overnight. Here's what you may have missed from the fourth day of Paralympic competition.

Gretsch gives U.S. its 2nd gold of Games, finishing 1-2 with Masters in biathlon 10km

Americans Kendall Gretsch and Oksana Masters went one-two in the 10km middle-distance sitting to each capture a second biathlon medal at the 2022 Paralympics; just three days prior, they finished a respective three-one in the sprint. Gretsch's title, matching her world-championship result from January, gave the U.S. its second gold of the Games.

The field's 10 biathletes slogged through slow snow with temperatures hovering around 40 degrees Fahrenheit. Gretsch missed a shot during her first of four visits to the shooting range and had to take a penalty loop, but the Illinois native made up time on the course – so much so that despite Masters' clean shooting, Gretsch still took the victory.

Gretsch won by less than nine seconds over Masters. though crossed the line about a minute slower in real time. That's because a factored timing system enables skiers with varying ability to compete fairly, multiplying their times by a percentage. Gretsch's sport class is LW11.5 and she competes at 96%, while Masters' is LW12 and competes at 100%.

Masters stayed perfect in the range at these Games, something she tried not to think about during the last bout but inevitably did. "I was totally thinking, 'Don't miss the shot,'" she said. She admitted that perfection cost her precious time, and praised Gretsch for her fast shooting, but nonetheless felt happy to redeem a DNF fall during the 2018 race.

Her silver marked her 13th overall Paralympic medal and third in three events at the 2022 Games — in addition to the aforementioned 6 km sprint gold from Day 1 of competition, she took silver Saturday in cross-country skiing's 15km long-distance sitting event. She plans to compete in four more events, with one more in biathlon and three in XC.

"It's going to be an incredible podium," Masters said. "I've got my teammate Kendall on top and an incredible athlete, [bronze medalist] Anja Wicker – she's been my influence in biathlon … She's who I embody, she's the queen of biathlon. I'm so happy to share this with Team USA and Germany on the podium."

Gretsch just missed the biathlon middle-distance podium in PyeongChang, then finished behind Masters with silver at the 2019 World Championships. In 2021, she became the first triathlete to claim gold in the women's wheelchair class at the Paralympics, winning the event's debut at the 2020 Tokyo Games. The 29-year-old was born with spina bifida.

REPLAY | RESULTS

Ukraine sweeps its second, third biathlon podiums of Games

Iryna Bui, Oleksandra Kononova and two-time reigning world champ Liudmyla Liashenko finished top-three in the women's 10km middle-distance standing for Ukraine's second sweep of the Games, joining the men's trio that swept Saturday's sprint vision impaired event, and repeating a rearranged podium of their January world-championship sweep.

"I'm really happy to share the podium with my teammates," said Bui, who twice finished fourth in PyeongChang. "We would like to dedicate our results and medals to each and every Ukrainian and all the soldiers in the Ukrainian army who protect us … we represent the whole country, and this is our battle, here."

REPLAY | RESULTS

Later, Ukraine took the top five spots in men's vision impaired, adding another medal trifecta in the same classification that produced the first on Saturday. Vitalii Lukianenko, 43, the sprint winner, found gold again for the eighth time of his career and shared the podium with compatriots Anatolii Kovalevskyi and Dmytro Suiarko.

Both Lukianenko and Suiarko dedicated their medals to the women of Ukraine on International Women's Day, with the former saying he "want[s] to wish them a peaceful sky over their heads, and to be happy in life and not to cry like they do now in Ukraine."

Suiarko, a native of Chernihiv, said it has been very hard to concentrate with the ongoing situation back home. He said he "missed twice because yesterday my house where I live, it was bombed and destroyed."

At the conclusion of the day's medal events, Ukraine had 17 medals and six golds, both No. 2 behind China in the count. Sixteen of those medals and five golds have come in biathlon.

REPLAY | RESULTS

Liu Mengtao earned China its third biathlon gold and eighth overall of the Games with a victory in the men's sitting event, while Canadian Mark Arendz grabbed his ninth Winter Paralympic medal by winning the men's standing.

In the vision impaired events, 18-year-old Leonie Maria Walter of Germany added a gold to her two bronzes won earlier, upsetting favorite Oksana Shyshkova of Ukraine, who entered as the event's defending champion with a pair of golds already earned at the Games. 

Aside from Gretsch and Masters, Americans struggled at the distance. Lera Doederlein, 18, placed ninth in women's sitting, Dani Aravich was 11th in women's standing, and PyeongChang silver medalist Dan Cnossen and Aaron Pike took 12th and 15th in men's sitting. Pike and girlfriend Oksana Masters embraced during a break in the day's competition.

China routs USA in wheelchair curling

Fresh off a stunning comeback win versus Norway, the United States was unable to capture the same magic in its sixth round robin game, suffering a 10-2 blowout defeat at the hands of defending Paralympic gold medalist China. After a blank first end, the U.S. conceded a catastrophic five-point steal in the second end and was never able to recover. Misses by multiple American team members in several spots helped lower the team's round robin record to 2-4 with four matches remaining. The U.S. will likely have to run the table in order to qualify for a semifinal spot.

FULL REPLAY

South Korea pulled off an upset by handing 2018 Paralympic bronze medalist Canada — which entered Tuesday's competition as the top-ranked team at 4-1 — a 9-4 defeat. The South Koreans stole four to start before the Canadians finally put points on the board in the fifth end. They then tallied four more in the sixth to go up 8-2, which proved to be insurmountable. The result was Canada's second straight loss after starting round robin play with a 4-0 record.

Canada locks up spot in sled hockey semis on final day of prelims

With each team seeking a first win after dropping openers to the U.S., Canada nearly repeated the 7-0 rout it had over South Korea the last time the two teams faced off during the 2018 Paralympic semifinals. This time, for a chance to progress directly to the semifinals with an automatic bye, it was 6-0.

Liam Hickey started things off in the first period for Canada, and James Dunn followed up with a beauty to make it 2-0, then added another in the second. The Canadians found the net three more times in the third with goals from Billy Bridges, Tyler McGregor and another from Dunn to complete his hat trick.

In the second game of the day, China's Wang Zhidong scored against Italy within the first 16 seconds. His teammates Bai Xuesong and Qiu Dianpeng followed suit before the four-minute to go up 3-0, and Hu Guangjian tacked on another before the first period expired. China recorded two more goals to win 6-0 and improve to 3-0.