Well the weather was bad on that day, (insert another random excuse here) Liverpool had there whole team injured and the football wasn't the same type as the premiership.
On a serious note, Liverpool were outplayed on that day. I think though, and many would agree Liverpool are a better team than Florientina. This is what makes football special, Liverpool beat ManUTD one week lose to Fulham the next. Teams form varies throughout a season, it happens to all teams ManUTD Chelsea Liverpool. You name the team and their form will dip at some point. Class always comes through hence the top leagues always finish with the same names.