Rodriguez was expected to make a comeback before the end of 2014 after rupturing an anterior cruciate ligament against Manchester City in April, which ruled out of England's World Cup squad in Brazil.
But Southampton manager Ronald Koeman is now set to be without the 25-year-old for another few months.
"He has had to take a step back in his recovery and that was a pity," Koeman said.
"When we spoke about the squad in the pre-season, we said he would be a fantastic sign-up for December and January and he isn't.
"All these injuries are making up the difficult time we have, but he needs time. We will give him that time. It is a pity because he is a great player.
"It is not good to fix on a special date when he will come back. He is making steps forward and needs more time, but I don't want to put pressure on the player and the medical staff."
"He will not be available before the end of January."
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