Liverpool midfielder Lucas Leiva has been ruled out of the rest of the season with a knee injury. The former Gremio man was carried off on a stretcher in the second half of the Reds\' 2-0 League Cup quarter-final win at Chelsea on Tuesday. Manager Kenny Dalglish\'s worst fears were confirmed after a scan revealed damage to the anterior cruciate ligament in the player\'s left knee. \"The Brazil international will undergo surgery and unfortunately be ruled out for the remainder of the current campaign,\" said a statement from the club.