Chelsea signs New England Revolution goalkeeper Djordje Petrovic for record $17.5M transfer fee

Petrovic initially wanted to transfer to Nottingham Forest or Nantes but New England delayed until Chelsea made record offer.
Transfer fee of $17.5M sets new MLS record for a goalkeeper.
Chelsea sees Petrovic's potential to succeed in Premier League.
Petrovic is considered among best goalkeepers in MLS.
Transfer is among most expensive outbound deals in MLS history.