As Paralympic action gets underway in Tokyo, you may see some sports on the schedule that make you do a double-take.
Twenty-two sports will be contested, with 128 Canadian athletes and guides partaking in 18 of those.
Here are some explanations to help you better understand what you're watching:
One of two Paralympic sports without an Olympic equivalent, goalball is played only by the visually impaired. Teams of three line up on a playing surface the size of a volleyball court, with nets lining the width of the hardwood.
Teams take turns throwing a ball roughly the size of a basketball and equipped with bells into the opponents' net. There are no goalies — all three players are responsible for both attacking and defending over the course of two 12-minute halves.
It's the bells that inform much of the on-court strategy. Attackers can attempt to beat their opponents on throws with velocity, though that allows defenders the advantage of using the sound of the ball to make a save. They can also slowly roll the ball, limiting noise to try to sneak the ball into the net.
Because sound is so important to the game, the crowd acts as though it's at a golf tournament: silent during action, but loud when a goal is scored.
The goalball podium is open for the taking, as there is no dominant force in the sport. While Canada's men failed to qualify, its women's team is ranked sixth in the world and won gold in 2000 and 2004. Another strong entry will compete in Tokyo.
Boccia is the other sport unique to the Paralympics. Its closest comparable sport might be curling, from which it borrows some language. Boccia is played by athletes with disabilities that affect motor skills, and will be contested individually, in pairs and in teams of three in Tokyo. All events are mixed gender.
A white ball — referred to as a jack — is thrown to begin each end (team competitions are six ends long, with all others halted after four) after which each side takes turns throwing red or blue balls. The balls are slightly bigger than tennis balls and made of leather.
Scoring is the same as curling as one point is awarded for the ball closest to the jack, plus additional points for each ball closer to the jack than the opponents' closest ball.
Canada has one main medal threat in the sport: Alison Levine. Levine is the first woman to ever be ranked No. 1 in her discipline, and she'll hit the boccia court both as an individual as well as in the mixed doubles competition.
The name tells part of the story: there are five players, including a goalie, on each team, battling in a sport similar to Olympic football (or soccer, as it's known in North America). But in the Paralympics, it's played just by visually impaired men — only the goalie may be sighted.
The teams play on a field much smaller than a typical soccer field and surrounded by boards. There are no throw-ins or offside, which keeps play moving and avoids the need for the dreaded video assistant referee. Goalies can shout instructions to players on their teams, while each side also has one guide positioned in the attacking zone for the same purpose.
Like goalball, the football 5-a-side ball makes noises to assist players, and as such, the crowd must remain silent except for after goals are scored.
Brazil has won five of seven gold medals in the sport's Paralympic history, with Argentina taking the other two. Canada did not qualify a team to Tokyo.
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Here's all you need to know about this sport: it used to be known as "murderball." That's because while it uses the same general rules as rugby, it's the only Paralympic sport in which tackling is permitted. Add wheelchairs to violent rugby collisions, and you start to see where murderball came from.
One key difference from able-bodied rugby: players are classed into seven options depending on their functional ability. The higher a player's functional level, the higher their class. The highest class is 3.5, while the lowest is 0.5.
The combined classification value of an on-court team can't exceed eight points. So there's an added level of strategy in not only getting two wheels over the try line, but ensuring you keep under that cap.
Also, it's a mixed-gender event, and female players can allow teams to play with an extra half–point per player.
Canada qualified a team for the Tokyo competition. The country landed on the podium in 2004, 2008 and 2012, but lost the bronze-medal game in 2016.
Para taekwondo and Para badminton
Both sports were added to the Paralympic program for Tokyo 2020, which is why you may not have known of their existence. But they both operate under fairly similar rules to their Olympic counterparts.
Canada does not appear to have strong medal contenders in either.