It's a permanent deal which sees the striker return to the club he was on loan to last season.
Pizarro was a free signing for the Blues from Bayern Munich in 2007 and he made 10 starts with 22 as sub, scoring two glorious goals.
Now all Chelsea have to do is get rid of Andryi Shevchenko.
Both cost Chelsea millions in wages and the money saved will go some way to signing a proper striker.
What do you think of Pizarro - will he be missed?
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