Arsenal and Barcelona are locked in a bitter bust-up over the former trying to snatch 16-year-old wonderkid Jon Miquel Toral Harper from their academy, just like they did with Gunners skipper Cesc Fabregas.
According to a Sun Sport report, the dispute erupted before both clubs clashed at the Emirates last Wednesday.
Barca president Sandro Rosell is said to have forcibly told Arsenal chief executive Ivan Gazidis to back off from bidding or snaring mid-fielder Toral, who has an English mother and is now close to signing a professional contract with the Gunners.
The bitter bust-up is now threatening to overshadow the return leg at the Nou Camp when Arsenal defend a 2-1 lead.
There is no suggestion the Gunners have done anything untoward but the Catalans are up in arms.
Rosell is particularly sensitive about this issue as he was vice-president when the Gunners nabbed Fabregas back in 2003.
Barcelona have been publicly tapping-up Fabregas for several years and last summer he was on the verge of returning to his hometown club in a £31 pound transfer, but Gunners boss Arsene Wenger blocked the move.
