The former Blues forward, who was offloaded to Besiktas in the summer, says he was not given a fair chance to prove himself at Stamford Bridge.
The Senegal striker joined Besiktas in the summer after struggling to get regular playing time at Stamford Bridge, with the signing of Diego Costa from Atletico Madrid further blocking his path to the starting XI.
Ba still scored a number of crucial goals during his time with the West London club and has suggested that he was not given a chance to prove himself to Mourinho, arguing that he was too often left playing second fiddle to the likes of Fernando Torres.
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He told the Daily Mail: "Sometimes when you are at a club with a lot of big stars, the name counts for more than the statistics. Unfortunately, it was like that in my case. But I am happy I moved from Newcastle to Chelsea and achieved what I did. I have lots of friends there. Eden Hazard is one of my best friends, I am close to Branislav Ivanovic, too. All my wishes are for them to win the league."
Ba is preparing to face Arsenal in Tuesday's Champions League playoff first leg and the former Newcastle man, who came close to joining the Gunners before Mourinho pulled the plug, can understand why his move to the Gunners did not go through.
He added: "I always said the move to Arsenal was close. I thought the deal was done and I would just go and do the medical but it went another way. Jose has said why it didn't happen. He was honest; he just didn't want to give them a striker who could score goals, especially with the arrival of [Mesut] Ozil. Now I am playing Arsenal in such a big match. It's crazy, but I have no regrets about everything that happened.
"Our team are very young and still learning. We will have a very tough game against Arsenal but we want to go through to the Champions League spot and get the six matches in the group stages. The caliber of Chelsea's forward players is a little different, but we have a lot of young players who are very quick and very comfortable with the ball. Maybe we can learn from the Arsenal game at Chelsea and cause damage in the same way."