Iniesta, 36, underwent successful surgery in Barcelona.
The injury occurred in last week's ACL quarter-final against Suwon.
Iniesta said in a statement on Instagram accompanied by a photo of himself in a hospital bed that he had broken the "rectus femoris of my right leg".
"After many tests I took the advice of my medical team and we have considered that the best option for me was to get surgery and speed up the recovery.
"The surgery has been a success and I am feeling very well."
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