Click to enlarge, and debate the strip below the line.

Keith Hackett's verdict

1) Yes. The fact that he was off the field when the ball was last played is not relevant: he is considered to be on the touchline and therefore in an offside position. The moment he becomes active, you must penalise offside. David Grace wins the shirt.

2) Not the most sporting of opponents, are they? Assuming the injury is clearly genuine, stop play and re-start with a dropped ball – which the opponents, once they have cooled down, may realise it is sensible not to contest. Thanks to Peter D Smith.

3) This is expressly not a situation where you need to be thinking about offside or outside agents interfering with play. Clearly you should be treating this incident, with the striker on the ground and unable to move, as a serious injury, in exactly the same way as if it was a clash of heads. So stop play and call for medical assistance for the player, restarting with a dropped ball at a point on the six-yard line parallel to the goalline nearest to where he fell. Allow him to come back on later, if you are satisfied the false leg is secure. Thanks to Richard Burton.

Competition: win this week's original artwork

To mark the 200th online You are the Ref strip, we're offering you the chance to win a unique collectors' item: this week's original signed artwork. To enter, read Trevillion's guide to how he created this week's portrait of Mario, then send us your own, of any player or manager.

A selection of the best hand-drawn portraits will be published online – with one overall winner, chosen by Paul, winning the prize. To enter, email your artwork to you.are.the.ref@observer.co.uk before 30 April. Terms apply.

How to draw Balotelli - by Paul Trevillion

Some faces are a real gift for an artist, and Balotelli's is one of them. He doesn't need to open his mouth: his face is so expressive – his character pours out of every line. It's one of those faces that would look magnificent in a cinema action epic on a movie screen 20ft high. What a warrior.

Stage 1

Balotelli Trevillion one Photograph: Observer

Balotelli's face is the opposite to Wayne Rooney's. Rooney's face is as high as it is wide. Balotelli's face is almost twice as high as it is wide. His forehead takes on the shape of a Roman helmet, his hair the plume. Every line that forms his face is an upward stroke. The hair points upward, the ears point upwards, the eyebrows point upwards, the flared nostrils point upwards and the few lines he has also point upwards. Only one line points down – the line of the mouth. Balotelli doesn't smile.

Stage 2

Rub out the proportion guidelines and then add just the few extra lines I have shown: that's all it needs and the face will start to take on character …

Stage 3

Black in the hair, the arched eyebrows, the flared nostrils, the open mouth and it's Balotelli.

Stage 4

To give it shape, darken one side a little more than the other. This will give an appearance of roundness. The white of the eyes should now begin to stare out in the familiar challenging Balotelli defiant manner.

Stage 5

Now add the colour. Don't splash it all over the face. Leave some white on both sides of the face, and at the top of the skull. You now have the classic Balotelli facial expression – staring at a red card, asking that trademark question: "Why always me?"