Spanish international Fabregas - who spent several years at Barcelona as a youngster before joining Arsenal - was initially delighted to return home to La Liga in 2011 but eventually became frustrated due to a lack of regular starts under previous manager Gerardo Martino.
Fabregas deserved better
Given his declining influence at the club and with a radical shake-up of personnel promised following the arrival of Luis Enrique, Barcelona appeared perfectly content to accept Chelsea's £30 million offer for Fabregas in June following Arsenal's slightly surprising choice to pass on the option of bringing the 27-year-old back to the Emirates Stadium.
And while the player obviously does not harbour any particular ill-feeling towards his former employers, Tello - who is technically still a Blaugrana player but will spend the next two seasons on loan in neighbouring Portugal with FC Porto - obviously believes he was worthy of a far better send-off.
"He (Fabregas) didn’t leave the club as he deserved," he said in an interview that was brought to our attention by the Daily Mail.
"He left through the back door. He was a spectacular player, you only have to see the goals and assists from his time at Barça. I suppose he will be hurting because his dream was to triumph at Barcelona."
Excellent Chelsea start
While he may have been disappointed to leave Barcelona for the second and surely final time, Fabregas has shown no signs of a potential hangover during the early stages of his career at Chelsea.
Along with fellow summer signing Diego Costa and irrepressible playmaker Eden Hazard, he has been a pivotal figure behind the Blues' rise to the summit of the Premier League and, if anything, looks a more complete player now than when he was earning regular plaudits as captain in North London.
Any doubts that Chelsea fans may have harboured regarding Fabregas' traditionally uneasy relationship with Mourinho have also been firmly extinguished, with the latter dubbing his new recruit 'fantastic' following the recent 2-0 victory over the Gunners at Stamford Bridge.
With Fabregas marshalling the midfield in typically impressive fashion, Mourinho's side have won six of their first seven games of the new Premier League season and can already boast a five-point buffer over reigning champions Manchester City.