Arsenal certainly face a tough test of their title credentials when they travel to Aston Villa on Saturday evening, another date with their former boss Unai Emery. It’s well documented that Villa stifled Arsenal and their title bid last season – Mikel Arteta wasn’t able to get the better of his compatriot home or away. But Arsenal are rejuvenated heading into their third serious attempt to beat Manchester City to the title, believing this could genuinely be their year. Arsenal agreeing a deal for Mikel Merino is a big boost in that regard, who could perhaps be announced as the club’s third sum…