The Spain international completed a reported £27m move to the Blues from the Catalan side in July, penning a five-year deal at Stamford Bridge.
Fabregas did reasonably well during a three-year spell at Barcelona, scoring 28 goals in 96 La Liga appearances and winning the La Liga crown in 2013.
And the midfielder’s former Barcelona team-mate Tello, who is currently on loan at Porto, hinted that Fabregas was forced out of the four-time European champions.
“Cesc didn’t leave the club as he deserved to,” Tello told Sport.
“He left through the back door. Cesc was a fantastic player and you only have to look at the goals he scored and the assists he provided in his time at Barcelona.
“I suppose he will now be hurting because it was his dream to be a success there.”
Fabregas has scored one goal and made eight assists in eight appearances in all competitions this season.
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