"Sam will hopefully be available for the Dragons game," said Blues director of rugby Dai Young.
"You've got to set yourself realistic targets. If things don't progress as quickly as possible, players don't play. It's as simple as that. We are not going to risk players.
"But Sam is moving along nicely and the Dragons game seems a sensible target."
His Welsh teammate Gethin Jenkins could also make his comeback in the clash after recovering from toe surgery that ruled him out of the entire Six Nations.
"We were hoping for Gethin to be available for this weekend's game, but he's not quite where he wanted to be," said Young.
"He's running. It's just that pressure point from the scrum is the issue more than anything.
"Realistically the target has moved back a couple of weeks to the Dragons game now."