For the moment, it looks like this could be Cristiano Ronaldo's last season for Real Madrid. The Portuguese player is not in great form and his comments when asked about his future have been enigmatic to say the least. All things considered, maybe it would be wise from Real Madrid to find a buyer, cash in some money and move on from the Ronaldo era. If that's Madrid's determination, Chelsea would be interested in the star, according to Diario AS.
Chelsea's owner Roman Abramovich would be willing to sell players like Hazard, Oscar or Matic in order to sign Cristiano Ronaldo. Hazard would seem like a good replacement but his form has been terrible this season as well, so Madrid could explore other possibilities.
However, it would be difficult to imagine Ronaldo playing for Chelsea if Mourinho remains their coach. Ronaldo himself said "why not?" when asked about whether he would like to be coached by The Special One again, but that doesn't seem very likely given how abruptly their relationship ended.