The Spaniard signed a five-year deal with the Blues in June after Arsenal turned down the chance to bring their former captain back to Emirates Stadium.
Fabregas has hit the ground running upon his return to the Premier League, making eight assists to help the Blues top the table.
And Palace manager Warnock feels that the 27-year-old is a more versatile player now than he was during his eight-year spell at Arsenal before his transfer to Barcelona.
“Fabregas was a great player at Arsenal but I think he’s matured since,” Warnock is quoted as saying by The Telegraph.
“He’s so much more decisive now, there’s an end product to his game whereas at Arsenal I didn’t think there was as much.
“He’s almost got the complete midfielder’s package now.”
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