Barnsley are currently in the Championship relegation zone and are five points off safety with seven games left to play.
Townsend, who had started eight of Barnsley's last 10 matches before losing his place to regular goalkeeper Adam Davies, is now unavailable to manager Jose Morais, who has won just one of his eight matches in charge since taking the reins in February.
"It was a duel between two players that resulted in him breaking his finger," Morais told BBC Sport.
The former assistant to Jose Mourinho insists he has no problem with two of his players clashing.
Morais added: "I'm not frustrated. If I could give a pair of gloves to both of them and say 'start to fight', they have a fair fight, and it would result in a better shape for the team and a better atmosphere, then I would say the result is good."
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