While impressed, Gullit wants to see how the midfielder performs after this first season's "honeymoon period".
"Palmer has fantastic numbers. He was a gift," said Gullit. "He's come in this first year and played all the games, which is great because I like to watch him."
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"I think he has huge potential, that's for sure. But he had a difficult time against Man City in the FA Cup semi-final. You forget he is still a kid. He is young and he's been huge for Chelsea this season but this is his honeymoon period.
"Let's see how he does after that. Let's see what happens next year because there will be real pressure (to deliver again). The team as a whole has to improve a lot next year too."