The Brazilian also reserved praise for Paolo Maldini and suggested that he has no plans to follow in the coaching footsteps of Clarence SeedorfAC Milan midfielder Kaka says Lionel Messi and Zinedine Zidane are the best footballers he has faced and Cristiano Ronaldo is the greatest player he has ever played alongside.
The Brazilian midfielder faced Messi numerous times during his time at Real Madrid, where he played alongside fellow Ballon d'Or winner Ronaldo.
Zidane was only involved in the set up at the Santiago Bernabeu while Kaka was there, but the 31-year-old's appearances against the France legend earlier in his career were enough to leave a lasting impression.
"The best ones I played against were Zidane and Messi," Kaka wrote in a Q&A via Milan's official Twitter page. "The best one I've played with was Cristiano Ronaldo.
"The strongest defender I've played with or against is Paolo Maldini [Kaka's former teammate at Milan]."
Kaka also expressed his delight at playing under Clarence Seedorf, who took over from Massimiliano Allegri as Rossoneri coach in January, but played down the chances of him following in the Dutchman's footsteps when he hangs up his boots.
"It's the first time a former teammate is now my coach," he said when asked what it's like playing under the ex-Netherlands international. "I'm so happy about it and I think Seedorf will do a great job!
"I would say no [to coaching in the future]. I don't want to coach once I retire from playing, but I do not know if I will miss being part of the field of play. Who knows!"