Would imagine Rodgers doesn't want to risk being turfed out of a winnable competition to lowly opposition after a dodgy start. Play the lads who need games (Markovic, Toure, Lambert, Jones, Enrique, Lallana) and then play some first teamers that you sub for other first teamers. Don't want to go into the derby with 1 win in 4 after having played Villa, Ludogorets, West Ham and Boro.