Morris and Lawes downed Switzerland's Jenny Perrett and Martin Rios 7-2 in six ends on Saturday before defeating Anastasia Bryzgalova and Aleksandr Krushelnitckii from the Olympic Athletes from Russian Federation team 8-2.
The teams got to the arena with little time to spare and had to rush through their practice session before a game against the United States.
Mixed curling is one of four new events at the PyeongChang Games, along with the alpine ski team event, speed skating mass start for men and women, and men's and women's snowboard Big Air.
Mixed curling is making its debut at the Olympics, and the basics are relatively simple. Team OAR could end up in any of the other 2-4 seeds based on Saturday night's games. And says that means that I'll watch it now but any other time of the year on ain't no way am which and people curling.
Norway had a stone approximately one inch closer to the pin than Finland, just enough to earn its fourth win and keep pace with Canada and the Olympic Athletes from Russian Federation atop the round-robin standings.
"When we were teenagers, obviously being so close in age and being angsty kids, we kind of butted heads as youth", Matt said.
Stormy parade weekend: Chance for some heavy rain
While there could be a few flurries late in western NH, the light snow will hold off for most areas until Friday evening. Temperatures will also plunge, with lows of -2C leading to a widespread frost and icy stretches on the roads.
"It's sure nice to have the evening off", Morris said. The latest win came in Draw 5 of the round robin portion of the competition, with Canada dominant in a 7-2 victory over Switzerland. "I don't think he missed a shot after that. We'll enjoy it from Canada House and who knows, maybe they'll have an extra beer I can sip on while I'm watching it".
"Unfortunately there's not free bingo spaces here", Lawes said following the loss to Finland.
"I call most of the shots, but Becca just lets me do that because most of the time we agree", he explained.
In addition to qualifying for that event, Becca, 27, and Matt, who turns 29 during the Games, are also part of the US men's and women's teams in PyeongChang.
With two rocks on the red zone of the target to start the ninth end, Finland was in prime position to get a much-needed win.
Morris won Olympic gold in 2010 playing third for Kevin Martin, while Lawes topped the podium in 2014 as vice for Jennifer Jones. "I'm really proud and honoured to be a part of this".