There are 12 players on a team: one must be female
(although not necessarily used), and there are four on the court at any one time (unless they receive a suspension for an infringement of the rules and have to sit on the sideline for one minute while play continues). Each player has a points rating based on their disability and there can only be a certain number of points on the court at any one time, so substitutions have to be well planned.
It starts (and indeed finishes) in a gentlemanly-enough way, forming a line to shake hand with each of the opposition. 
Then the fun begins, as they fight it out in four eight-minute periods, with the aim to carry the ball over the opposition's line to score a goal - or stop the opposition doing likewise by stealing the ball, blocking or simply knocking each other over. Coaches can call 'time out' to give the team time to regroup or discuss tactics...
...and we saw more than one 'pit stop' - needed when a collision was so fearsome that a wheel was bashed out of alignment or got a puncture and needed replacing. 
Of course they come well-prepared, with plenty of replacements lined up on the side just in case. 
Tactics are paramount - jostling for position as the ball is put back in play after a goal has been scored 
or ganging up on someone from the opposing team to put them out of the game. At times it was almost balletic, as players shadowed every twist and turn, anticipating a sprint down the court to receive the ball and score... 
...at others it was more like the scrums of rugby we know - lots of players bunched together aiming to block or steal the ball 
But the part the crowd seemed to relish the most were the truly crunching 'tackles', leaving one player toppled on the ground and needing a coach to help them back upright:
the gasp, hush and then cheer as they were put right was not uncommon through the match as players from both sides went down.
The break between the quarters were filled with blasts of music and encouragements to cheer, while the mascot Fu Niu Lele made an appearance at half-time, as the floors were wiped down (I wondered as much for blood as sweat). 
It was a tight match until the last quarter, when the Canadians pulled away, helped by some strong tactics and close defending of the line, eventually winning 48-40
Wheelchair Rugby makes for a great spectator sport - but it's certainly not for the faint-hearted.
