During his Barcelona days he branded the Blues "pathetic", reports the Sunday Mirror.
Eto'o, 32, made his views clear after he scored Barca's winner in a first-leg Champions League clash with Chelsea in February 2005.
Ahead of the return game, Eto'o said: "I would sooner sell groundnuts in my home village than play for a pathetic club like Chelsea."
His comments backfired, with the Londoners winning the return 4-2 for a 5-4 aggregate success.
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