Similarly to Costa, Spanish international midfielder Koke is another player whose form has been vital to Atletico's title charge.
The 22-year-old midfielder has scored four goals and provided eight assists in 19 league games this season and provided stability in Simeone's midfield with a number of admirably mature displays.
If Atletico were to lose Koke now, their season would surely suffer as a consequence. At 22, he has all the time in the world to make his next big move. Call me a dewy-eyed romantic if you wish, but I would love to see him remain in Spain until the end of the season to see if Atletico really can pull off the spectacular.