Olympic mixed doubles curling trials set for Portage la Prairie, Man.

The Olympic trials for the Canadian mixed curling doubles event will take place in Portage la Prairie, Man., Curling Canada announced Tuesday.

The event, which will be making its Olympic debut at the 2018 Winter Games in Pyeongchang, South Korea, is scheduled for Jan. 3-7, 2018.

Eighteen teams will complete for the chance to represent Canada at the Olympics (Feb. 9-25, 2018).

Meanwhile, the Roar of Rings Olympic trials, where the teams of seven men and seven women will compete to represent Canada, will take place in Ottawa from Dec. 2-10.

"This will be an historic event, and we're thrilled to see Portage la Prairie earn the privilege of playing host to the first Canadian Olympic Mixed Doubles Trials," said Peter Inch, Chair of Curling Canada's Board of Governors.

"We know the community will embrace this event, because we've seen Portage la Prairie step up repeatedly in the past for the sport of curling. Knowing what's on the line next January, we're anticipating a great show in Portage la Prairie."

Canada earned an Olympic mixed curling spot this past weekend in Lethbridge, Alta., as Joanne Courtney, of Edmonton, and Winnipeg's Reid Carruthers secured the berth by reaching the semifinals at the world mixed doubles championship.

Courtney and Carruthers went on to earn a silver medal. 

"Our mixed doubles athletes have been working extremely hard in the past few years to make sure we're at a level to compete for a medal in Pyeongchang," said Curling Canada's national mixed doubles coach Jeff Stoughton.

"That hard work will continue as we turn our focus to the Olympic season. And while Joanne and Reid clinched the berth this past weekend, it's important to acknowledge the amazing and gutsy performance by Marliese Kasner and Dustin Kalthoff at the 2016 World Mixed Doubles Championship. Without the qualifying points they earned us there, we wouldn't be in the position we are today."

The Olympic trials will feature 18 teams, divided into two pools of nine, and eight teams will move into a modified double-knockout playoffs.

The setup

Here's what you need to know:

The basics are relatively simple. Each team consists of only two players — one man, one woman. Each team throws five stones per end, with the player delivering the team's first stone of the end also delivering the team's final stone of the end. The game lasts eight ends. The scoring is the same as in regular curling.

Then it gets a little more complicated.

The major difference between regular curling and mixed doubles is the positioning of two stones — one per team — before the beginning of each end. These rocks can end up counting for points if they make their way into the house.

The team with the "hammer" (last rock) chooses where to place these two stones. If that team elects to place its stone in the back of the 4-foot circle of the house and the opposing team's stone as the centre guard, then the opposing team delivers the first stone of the end. If it opts for the reverse, then it delivers the first stone of the end.

A modified version of the free guard zone is also in effect: no stone in play, including the "positioned" stones, can be taken out prior to the delivery of the fourth stone of each end.

The power play

Canadians know all about a power play in hockey, but here's how it works in mixed doubles curling.

The power play can be used once per game by each team, when it has the decision on the placement of the "positioned" stones (though it's not allowed if the game goes to an extra end).

When the power play is invoked, the in-house stone (which, remember, belongs to the team with last stone in that end) is placed with its back edge touching the tee line, with half of the stone resting in the 8-foot circle and half in the 12-foot. The guard stone is positioned to the side of the sheet so it protects the in-house stone.