The idea of a footballer refusing to leave the pitch when substituted is a staggering one in itself. Yet doing so in the dying minutes of a major cup final, and eventually forcing a manager to back down, would usually be inconceivable.
It may still be a rarity, but players disobeying instructions when asked to come off the bench is hardly unprecedented. Cristiano Ronaldo stormed down the Old Trafford tunnel instead of entering the fray for Manchester United as recently as October.
Former Manchester City star Carlos Tevez sparked similar controversy during a Champions League match away at Bayern Munich in 2011.