Deco admits he was down in the dumps after going three years without a trophy at the Estadio do Dragao, but when the self-styled 'Special One' took over he changed the mentality of the club and took them to UEFA Cup and Champions League glory in successive seasons.
'Before Mourinho arrived the players were sad,' Deco said in The Sun. 'I was inconsolable as I'd gone three years without winning the league title.
Thankful: Deco (left) celebrates with Blues team-mate Frank Lampard
Mr motivator: Jose Mourinho
'Jose Mourinho was contagious in his way of being and working. We started winning matches straight away and soon felt it was possible to win the league. We played beautiful football.'
Deco is set for a reunion with his old boss when his latest club Chelsea face Mourinho's Inter Milan in the Champions League on Wednesday.
And Deco warned his team-mates not to take his mentor lightly.
He said: 'He's fantastic at analysing opponents and defines the way to play against them.'
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