The Spanish midfielder is set to miss the first two matches of next season plus the final game of this campaign at home to Sunderland on Sunday following his first half dismissal after he kicked the ball against Chris Brunt.
Mourinho felt that a more experienced referee than Mike Jones would have resolved the situation with a mere lecture after tempers flared following a Diego Costa and Gareth McAuley off the ball coming together 29 minutes into the action at the Hawthorns.
“I’ve not seen a sending off like that,” said Mourinho.
“I would like to see it again. What is this for a sending off? Where is the danger of the situation to get a red card in a friendly game almost?
“I don’t understand. Darren Fletcher was aggressive yes, he pushed in the chest. He’s experienced. It was much more aggressive than what Fabregas did.
“A top referee with big personality has a few words and controls the game. It’s a bizarre red card.
“Three game ban for this? Jesus Christ. Of course it’s harsh. We lose all the time (when we appeal) but I’ve not spoken to him.
“Diego Costa was targeted, of course. But it’s the same story.
“It depends on the referee. If the referee wants to protect the talent and punish the bully it is easy for him.
“Congratulations to West Brom for the season and this three points. And let’s go home.”
Mourinho felt this first defeat in 19 matches was the net result of claiming the title three games ago as Saido Berahino scored on nine minutes and added a penalty two minutes after the break before Brunt scored a third on the hour.
“The ideal scenario is to be champions and don’t play again, go home and have holidays,” he said.
“When you have three more matches it can happen with Bayern Munich three defeats in three and we claim one point in two.
“When you play since August with motivation and commitment and feeling the pressure, when you are champions you breathe and everything changes.
“It is difficult to play. Let’s blame the players a bit, myself and the top contenders for the title as they were not good enough to fight with us. This is a consequence of being champions so early.”
West Brom manager Tony Pulis insists any criticism of Chelsea is unwarranted.
“It’s a great finish, we will finish 13th in the table but I don’t think anything should be taken away from the team we played,” he said.
“The team we’ve played have been by far the best team in England. They have won the league by a country mile and they have been much better than anyone else.
“Although we have won this game, all the praise should go to Jose, his coaching staff, the people of Chelsea and the players.
“Jose was very good. I’ve managed against him twice and managed to beat him twice with Palace and West Brom.
“He was very gracious in defeat and for all what we have done, they have been worthy champions. They are a fantastic football club with wonderful players and for some people to criticise them is unbelievable.
“We were so on edge after we lost at home to QPR and Leicester but the lads have bounced back.
“The attitude has been wonderful, we got the breaks in this game, we played really well at times and defended well. The discipline was good and we made it very difficult for Chelsea.”