Merida, who was once described by Arsenal manager Arsene Wenger as "an absolutely amazing player", made just six league appearances for the Gunners.

And the 20-year-old midfielder, who came through the youth system at Barcelona, opted for a move back to Spain with Atletico, the club he has supported from a young age.

"I'm an Atletico fan and I feel enormously proud to be here," he told AS.

"Atletico is a big club and so is Arsenal, but there were some circumstances there, particularly on the sporting side, which I wasn't happy with and I couldn't fit in.

"I made Wenger aware of that and as soon as I knew Atletico were interested, I didn't think twice."