Liverpool suffered defeat in their first match under new manager Arne Slot.
The Dutchman arrived at Anfield on a three-year deal from Feyenoord after replacing Jurgen Klopp and officially started work as head coach on June 1.
The new era at Anfield officially got underway last week with Slot and his backroom staff putting a host of players through their paces after they returned from their holidays.
And preparations for the new season intensified on Friday as Liverpool took on Championship side Preston in a behind-closed-doors pre-season friendly.
The Reds were defeated 1-0, with Robbie Brady scoring the only goal of the match from long distance.