Barcelona are fuming over Arsenal's move for teenage sensation Gerard Deulofeu.
The Daily Mail says Gunners chief scout Steve Rowley was in Switzerland earlier this month to run the rule over the talented 17-year-old during Spain's Under 19 European Championship qualifying campaign.
Rowley's spying mission on Deulofeu, who has been likened to Lionel Messi and Ronaldinho, was a significant step in Arsenal's plan to sign the youngster before his 18th birthday next March.
Footballers in Spain are not permitted to sign professional contracts until their 18th birthday - a rule Arsenal first took advantage of in 2003 by signing Cesc Fabregas from Barcelona when he was 16.
Just last month Hector Bellerin and Jon Miguel Toral Harper, both 16, joined the Gunners from Barca's La Masia academy. Ignasi Miquel and Fran Merida also swapped Catalonia for north London during Wenger's tenure.
