"Lennon felt the tear. He has no chance for Thursday," Redknapp told reporters. "He felt it go. It will be weeks if it's a tear."
Tottenham play Chelsea, two points behind them in fourth although Spurs have a game in hand, at White Hart Lane on Thursday.
Lennon went off after 27 minutes and was replaced by Russian Roman Pavlyuchenko, who scored the 61st-minute goal.
Pavlyuchenko has not started a league game this season but Redknapp said he wanted the 30-year-old to stay despite being linked to a move in the January transfer window.
"I'd like to keep him. People say Pav is going and we're looking for a striker but it is difficult to find anyone better," he said.
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