#1 Juan Mata - Chelsea (2011-2014), Manchester United (2014- )

Juan Mata was another curious sale by Chelsea to Manchester United, as prior to his departure from Stamford Bridge in 2014, the Spanish international had distinguished himself as one of the club's best performers and was named Chelsea Player of the Year in his first season with the club (a title he defended a season later).
Having won almost everything winnable, Juan Mata is one of the most decorated players of his generation and most of his successes came at Chelsea with whom he won the Champions League in 2012, while his international medal haul is also enviable.
At Manchester United, Mata has gone on to play his way into the hearts of the Old Trafford faithful and has made over 200 appearances in all competitions for the Red Devils, winning the Europa League, FA Cup, and League Cup.
Even though his career has been limited to sporadic appearances of late, there is no denying that Juan Mata made an impact at both Manchester United and Chelsea.