On Friday, Italian journalist Emanuele Giulianelli revealed via his Twitter page that the Valencia defender will undergo a medical at the La Liga club on Monday ahead of a move to north London.
Arsene Wenger was criticised last weekend for his failure to sign a new centre-half after Per Mertesacker, Laurent Koscielny and Gabriel Paulista missed their Premier League opener due to fitness problems.
The Arsenal manager was forced to start with England Under-21 defender Calum Chambers and summer signing Rob Holding at centre-half and Liverpool eased to a 4-3 victory over the Gunners at the Emirates Stadium.
But Sky Sports’s La Liga expert Balague has warned Arsenal supporters that Mustafi isn’t a top-class signing after the Spanish journalist expressed his reservations over the defender.
“I do not think Mustafi is good enough for Arsenal but there are not many good centre-backs available in the market right now. He would be a slight improvement on their current centre-backs but he is not worth the fee suggested,” Balague told Sky Sports News.
Arsenal haven’t won the Premier League title since 2004 when Thierry Henry and Patrick Vieira inspired the Gunners to an unbeaten season.
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