Great Britain's men won one and lost one as the GB women were defeated on day one of curling at the Sochi Games.
David Murdoch's rink scored four points in the sixth end as they beat Russia 7-4, but suffered late on as world champions Sweden beat them 8-4.
GB's women also lost to Sweden, beaten 6-4 by the women's Olympic champions.
Skip Eve Muirhead was off her game, with a shot accuracy of 61% whereas Sweden skip Margaretha Sigfridsson was higher at 80%.
Britain, considered strong gold medal contenders, have plenty of time to make amends with eight more matches in the round-robin stage of the competition, with the top four advancing to the semi-finals.
Muirhead said: "It is always disappointing to lose the first match. It was always going to be a tough one anyway, playing the European champions and world runners-up.
"They are one of the favourites but the game could have gone either way.
"We got off to a bit of a slow start, managed to claw it back to all square but they played a fantastic shot in the seventh end that gave them that step ahead."
Following the men's defeat by Sweden, Murdoch told BBC Sport: "We need to take the positives from it.
"It's been a fairly good day, a good win this morning on fresh ice, and we weren't quite precise enough tonight."