Reading manager Nigel Adkins admitted that Alex Pearce's red card in their 2-0 defeat to Sheffield Wednesday "cost" his team.
Pearce was dismissed after he brought down Jacques Maghoma in the box 10 minutes into the match.
Chris Maguire converted the penalty, before Benik Afobe sealed the points for Wednesday.
Adkins told reporters: "I'm not sure if it was a penalty, and it was the wrong decision to send Alex off, it changed the complexion of the game, it cost us.
"I'll have to think about whether we appeal the Pearce red card, as it stands I think we may do.
"Overall it's a shame because the players have been working hard and we've had good momentum."
The defeat was Reading's second in six games.
