Mourinho is keen to make several big moves in the transfer market, and needs to raise funds through the sale of key players to bring in his preferred targets.
Moves for Manchester City's Edin Dzeko and Fiorentina's Stevan Jovetic have been mentioned, but Mourinho would need to make space in the Chelsea squad for a new forward first.
That makes Fernando Torres in particular vulnerable. The Spain international enjoyed his best goalscoring season at Stamford Bridge last season, but is still some way short of his best form.
And could be offloaded to make way for a big-money striker. Chelsea's other options include Demba Ba and Romelu Lukaku, but Mourinho is thought to be keen to add an established Champions League striker to the squad.
In contrast, Juan Mata is in the form of his life, and was recently named Chelsea Player of the Year and Players' Player of the Year after a stellar campaign.
Mata led the Premier League with 12 assists, and was named in the top flight Team of the Season.
But the 25-year-old has been linked with a return to Spain, and the Marca report claims Mourinho would be willing to listen to offers for the former-Valencia playmaker.