On the latest edition of Essential Football, Jamie Carragher joins Ron Walker to preview this weekend's Merseyside Derby between out-of-form Liverpool and Sean Dyche's Everton.Carragher assesses why Liverpool have hit what he calls their worst spell under Jurgen Klopp, how he's trying to fix it and whether he might repeat his Dortmund exit and call it quits at the end of the season.He also looks at what Sean Dyche has already changed at Goodison Park, whether this is the ideal time for him to take his Toffee side to Anfield and how quickly he can turn things around at the club.