Click to enlarge, and debate the strip below the line.
Keith Hackett's verdict
1) The key here is that the substitution has technically been completed: one player has left the pitch and another has entered it. So the manager cannot choose a different player from his bench to go on instead. You need to ensure the injured player is treated and removed, then show the departed player a red card for violent conduct. If the replacement had not put one foot on to the pitch a different sub could have been sent on in his place – but as it is, his side are now down to 10 men. Thanks to Paul Hawkins.
2) We saw this sort of scenario at Spurs last week: a dreadful error. How you deal with it, as the referee, depends on whether you realise your colleague has made a mistake in real time. If you do, signal and shout "play on" – the striker should not stop playing until he has heard your whistle. But if not, and you wrongly accept the incorrect flag, you can only apologise and re-start with a dropped ball. Jason Chau wins the shirt.
3) First, ask if an alternative strip is available, or even a set of bibs, and if so, go ahead with the change. But if not, continue with the match anyway and report what was claimed after the game. And second, send the manager to the stands. He cannot be charging on to pitches to make his demands. Thanks to Keith Mason.
Competition: win a T-shirt of your choice
For a chance to win a Philosophy Football T-shirt of your choice from the Guardian range send us your questions for You are the Ref to you.are.the.ref@observer.co.uk. The best scenario used in each new strip wins a T-shirt; Terms apply. For more on You are the Ref's history, click here.
