The Liverpool striker picked up the injury at the end of Thursday's training before the Europa League win over Bordeaux.
“I don't know too much about the situation because it was in the afternoon after training," said Klopp. "It's not a situation I saw but we trained in two groups, the starting line-up and the other players trained together in shooting.
“Of course we can now start to think about it because we had no time, it was really close to the game when the news came.
“No news in this moment, we have to wait.”