Which shirt number will Arturo Vidal wear at Barcelona?

Which shirt number will Arturo Vidal wear at Barcelona?

 Arturo Vidal dio sus primeros paso en el Camp Nou / | Rubén Moreno

The Chilean midfielder has signed a three year deal with the Catalan club

Chilean midfielder Arturo Vidal is officially a Barcelona player and was presented on Monday morning after passing his medical and signing his contract. At the presentation there was no shirt number on the back of the strip, which begs the question - which number will he be?

The two numbers he's preferred have been 23 and 9. He wore that at Bayer Leverkusen, Juve and Bayern Munich. Meanwhile for Chile Vidal has worn the No 8, which is possible at Barcelona after Iniesta left.

Open are No 7 (Arda), No 8 (Iniesta), 12, 15, 16 (Deulofeu), 19 (Digne) and 22 (Vidal). However Samuel Umtiti has 23.