Lennon risked infuriating Redknapp by taking himself off during the defeat after his manager asked him to carry on.
Redknapp had already used three substitutes at White Hart Lane when Lennon picked up the injury 14 minutes from full-time and eventually headed down the tunnel after telling the bench more than once that he could not continue due to an ankle injury.
The England winger, with Fabio Capello watching the match in the stands, left the ground in a protective boot on his left foot.
"I was hoping he could stay on but he couldn't and suddenly we were down to 10 men," Redknapp said. "We're not sure what the problem is. He just said he couldn't carry on and that was that.
"I didn't give him a nudge - I just said to him we would only have 10 men and could he play on, but he said his ankle was too sore.
"I don't want to say any more, I don't want to cause an issue. It's not about England - he's got big games coming up for Tottenham."