Arsenal star Mikel Merino started for Spain in their 3-0 win over Serbia in the Nations League. The 29-year-old has had a torrid few months. He suffered an injury in his very first training session at Arsenal and was sidelined until very recently. However, Merino is fit now and although he is yet to reach his peak fitness level, you can tell just how good a player he is. Against Serbia on Tuesday night, Merino started in midfield and was very, very impressive. The Spaniard got on the ball on plenty of occasions, was very tidy in possession and his first touch for a player of his size is just i…