The Spain star has donned the number at international level and during his time at Juventus.
And following his £70m move from Real Madrid in the summer, Morata opted for the vacant figure.
But an array of former Chelsea men have struggled to live up to their expectations with the No.9, especially forwards.
Mateja Kerman, Steve Sidwell, Khalid Boulahrouz, Franco Di Santo, Fernando Torres and Radamel Falcao have all flopped.
Morata has revealed the superstition even led to Chelsea stars pleading with him to choose another instead.
However, the 25-year-old has impressed so far, scoring six Premier League goals, and insists he was ready to break the curse.
“That was one of the first things I was told after turning up here,” Morata told FourFourTwo.
“Even the lads were begging me not to take that shirt because it was cursed, but I wanted it.
“I’ve done a couple of little things to avoid the bad luck that the shirt supposedly brings.
“Can I tell you what I’ve done? No chance. If I did that, the curse will come back!”
“Even the lads were begging me not to take that shirt because it was cursed, but I wanted it.
“I’ve done a couple of little things to avoid the bad luck that the shirt supposedly brings.
“Can I tell you what I’ve done? No chance. If I did that, the curse will come back!”
Morata almost joined Manchester United over Chelsea in the summer.
And the Blues’ No.9 is set to start against former boss Jose Mourinho at Stamford Bridge tomorrow
