On Thursday, Arsenal progressed to the quarter-finals of the Europa League, but thanks to UEFA’s cup-tied rule, Pierre-Emerick Aubameyang won’t be able to take part.

Thanks to his time with Borussia Dortmund, Aubameyang is cup-tied for the rest of the season, despite the German club’s exit from the competition.

Personally I think that’s a great shame, and not just because I’m an Arsenal fan. First I’m going to explain what the rule is and why it’s in place, then why I think we should get rid of it.

1What is the cup-tied rule?

In UEFA competition, any player who plays in the Champions League or the Europa League is ‘cup-tied’ for the rest of the campaign. That means they can only represent the club they first played for that season, with one exception.

The exception is that every club can register one cup-tied player per season, as long as that player’s club hasn’t played in – or dropped down into – the same competition as you.

For example, Henrikh Mkhitaryan played in the Champions League for Manchester United, so he can’t play for another Champions League club. However, he can play for Arsenal, because Arsenal are in the Europa League. Similarly, Alexis Sanchez couldn’t play for another Europa League club, but he could play for Manchester United.

As mentioned, there is a strict limit of one per season, so Arsenal couldn’t sign another Champions League player and play him as well.

That would’ve ruled out playing both Mkhitaryan and Pierre-Emerick Aubameyang. Unfortunately Aubameyang was already ineligible anyway, because Borussia Dortmund dropped down into the Europa League.