Deeney revealed he's been carrying the injury after scoring twice in victory over Newcastle United.
"He's an experienced player," said Pearson. "Troy has what I would call a 'grumbly knee' that he has to manage on a daily and weekly basis. This is nothing new, it's something which he's come to terms with and has to manage, so you may see him with a bandage today, but it's nothing new.
"We have days where we have a number of players who have to modify their training. When you ask me on a weekly basis about injury news, even players who are available week in, week out, there will be some within I think most clubs who have to manage long term physical difficulties and Troy's known about this for a long term.
"He's been available and he's contributed in a very comfortable way today."