The 24-year-old, who championed Uruguay to victory in the Copa America this summer, has missed all of the Reds' pre-season fixtures.
Despite the striker’s lack of preparation Anfield boss Kenny Dalglish has not ruled out a starting place against Sunderland.
"Luis will be back next week some time and we'll start thinking about him then,” said Dalglish. “We'll just see when he comes in.
"He's had a fantastic summer in the Copa America both as an individual and as a team player.
"We'll see how he is when he comes in and have a discussion with him. We can't predict what he is going to be like."
Meanwhile, captain Steven Gerrard, who has been released from hospital after being treated for an infection, will not be in contention to play until September.