The 19-year-old Blues defender broke a fibula and tibia following an innocent collision with Leeds goalscorer Luciano Becchio 64 minutes into the third round tie at Elland Road on Saturday.
"Will's young team-mates and friends are distraught, they were in tears out there," Blues boss Lee Clark said.
"I said, `Let's try and win the game for Will'. We couldn't quite do it but I thought we deserved to do so.
"We will give him as much care and support as possible and have him back fit and strong for next season.
"We should be celebrating a fantastic performance by my young players, but this is a real downer.
"I heard the snap and was hoping it was a shin pad. It was an innocuous one with two players going for the ball."