Tube Polo was designed so that you didn’t have to be a strong swimmer. Players sat in inflated inner tubes, and pushed themselves around the pool with their hands. The teams took up their positions. The umpire blew her whistle and chucked the ball into the middle of the pool.

Both teams splashed towards it, eager paddling hands sending up clouds of spray. Mia was at the back of the Yellow team. A boy on her team got to the ball first. He quickly passed it but a girl on the Red team caught it and chucked it to another boy on the far side of the pool.

Half the Yellows started to paddle-charge towards him – but not Mia. Mia had worked out that the Reds would have to pass it again, so she might as well stay put and wait.

Sure enough, the ball suddenly flew out of the mass of laughing, splashing kids towards her. Mia grabbed it with both hands. She dropped it onto her lap, and started to paddle as hard as she could towards the far end.

The whistle blew.

“Mia! That counts as carrying.”

The Reds cheered, and Mia’s jaw dropped.

“I’m not carrying! I’m not using my hands!”

“Mia, you can only touch or move the ball with one hand, unless you’re the goalie. I did say! Free throw to the Reds.”

“Oh, that is so unfair …” Mia muttered.

But the Reds got their throw, and it soon led to the first goal of the game. Mia felt she was getting dirty looks from the other Yellows.

“How should I know it counted as carrying?” she moaned. But no one was listening.

Mia spent the next couple of minutes in a sulk. The ball flew back and forth between the teams and the sides of the pool.

Then suddenly it splashed down in front of her.

Mia scooped it up with one hand and looked around for a Yellow to pass it to. But she was surrounded by Reds, all paddle-charging towards her like a fleet of battleships.

Suddenly Mia felt herself sinking. Her tube was leaking. She could hear the hiss and see the bubbles as air squirted out of the valve. In a moment she was up to her waist in water.

“Sinking!” she shouted. “Not fair …”

All the Reds arrived at the same time. Someone snatched the ball away. Mia kicked herself away from her deflated tube, but the other tubes all around her made it impossible to see anything.

In a moment the umpire would have to blow her whistle for time out. The game couldn’t go on if one of the players was out of action.