Liverpool defender Daniel Agger could be ruled out of this week's League Cup encounter against Manchester United due to a rib injury.

The centre-back was substituted in the second half of the Reds' 1-0 defeat to Southampton on Saturday due to discomfort.

Manager Brendan Rodgers has revealed that he will make a late decision on the availability of Agger ahead of tomorrow evening's match at Old Trafford.

"We'll see how he is for the game," the Liverpool Echo quotes Rodgers as saying. "He could be a doubt for that game as he has not quite recovered.

"We wanted to give him time at the weekend, but unfortunately he was struggling with his breathing because he got a knock to his ribs, but we'll see. He's a player who makes a good recovery and we'll see over the next 24 hours how he gets on for the game on Wednesday."

Liverpool have already beaten United this season by seeing out a 1-0 win at Anfield in the Premier League.