#3 Karim Benzema
Marca has recently reported that Pep Guardiola wanted to sign Karim Benzema back in 2008, when he was appointed as the Barcelona manager. Txiki Begiristain, the then-technical secretary at Barcelona, even visited Benzema’s house in order to convince the Frenchman to join the club. But the deal didn’t materialize due to some bad review comments from the Barcelona director.
A year later, Barcelona swapped their then-prolific No 9, Samuel Eto'o with Zlatan Ibrahimović of Inter Milan. But Zlatan had to leave the club due to his differences with Guardiola, with Barcelona then signing David Villa from Valencia.
However, Real Madrid sneaked into the conversation of luring Benzema to Spain and got him on board in 2009. Since then, Benzema has been a regular starter for Los Blancos, and it's fair to say that Barcelona missed a golden opportunity to sign a top-class striker.