Manchester United boss Sir Alex Ferguson is refusing to dwell on the loss to Liverpool as he prepares his team to face Blackburn. A 2-0 defeat at Anfield last weekend saw United stay behind Chelsea at the top of the Premier League table, but Ferguson is intent on looking forward, not back and was encouraged by his side's midweek victory over Barnsley in the Carling Cup. However, he could be without defenders Nemanja Vidic and Rio Ferdinand, who both have calf injuries. Ferguson said: "They will both want to play after the disappointment of last Sunday. But then we had the game on Tuesday. You have to get on with life." The Scot added: "Vidic has been bothered with his calf for a few weeks now. We have sent him to a specialist about it. We will see what he is like today." Darren Fletcher has returned to training following a groin strain and could be involved against Chelsea next week. Meanwhile, Ji-Sung Park is still struggling to overcome a knee problem. Ferguson said: "We are just having a little issue with Ji-Sung Park and his fitness. "When he came back from his last trip to Korea he had no problem in the game but during the travelling he developed a swollen knee, which we don't quite understand. "We have some issues with that."