Allen, who marked his World Cup debut with a hat-trick against Uruguay yesterday, suffered the injury during the game and will be replaced by Newport Gwent Dragons centre Tyler Morgan.
Morgan, who was part of the Rugby World Cup training squad, will link up with the squad today.
“It’s disappointing to lose Cory in this way, especially following his man-of-the-match display against Uruguay,” said Wales head coach Warren Gatland.
“Tyler was part of the our extended squad and trained very well and will link up with us in London later today.”
Morgan replaces Allen in RWC squad
Wales centre Cory Allen has been released from Wales’ Rugby World Cup squad with a hamstring injury.
