Ward watched in horror as his Republic of Ireland international team-mate was stretchered off during the Clarets' 1-0 defeat at Leicester City on Saturday.
Brady was hurt in a collision with Leicester defender Harry Maguire and looked to be in some distress as he immediately signalled to the bench for medical attention.
He was taken to hospital for scans on his knee to reveal the extent of the damage, but boss Sean Dyche feared the worst when he spoke to the press after the match.
Ward is hoping it isn't as bad as it looked and acknowledged how much the team will miss the winger if he is forced to sit out a big chunk of the season.
"Obviously we don't know the extent of it yet but it didn't look great," he told reporters.
"Fingers crossed that it's not as bad as it looked. He's been outstanding for us recently and if it is bad he'll be a massive loss for us.
"It would be a massive blow. We'll await the news and we wish him well because he's been great for us. He's great to have in the dressing room too so our thoughts are with him if it is bad.
"It's another test for the squad but we've dealt with these kind of set backs before."