Arsenal take on Chelsea tomorrow with one of the big stories ahead of the game being the presence of former Arsenal captain and fan favourite Cesc Fabregas.
Chelsea signed Fabregas from Barcelona for a fee of €33 million. Barcelona had made it clear that they were not hoping to keep hold of the player this summer, after reportedly believing he had not settled back at his boyhood club.
But Arsenal of course had the buy-back option on the player - which they did not exercise.
It seemed an odd decision from Arsene Wenger. The pair have an excellent relationship, and have done since Fabregas was just a boy.
As the above photo shows the two were working together when Fabregas was as young as 16. He was a member of the Arsenal first-team at the tender age, making his debut against Rotherham United in October 2003 - not long before this photo of Wenger instructing his new protege was taken.
Fabregas of course went on to play over 300 games for Arsenal and was their captain when he made the decision to join his beloved Barcelona in 2011 - reportedly with the reluctant blessing of his long term mentor.
But a little over 11 years after this photo was taken Fabregas now aims to get one over on his former boss and team. If he does you can only assume it will be like a dagger to the heart of Arsenal fans, and Arsene Wenger.