Goals from Luis Alberto, Iago Aspas, Martin Kelly and Raheem Sterling were more than enough for victory but Giancarlo Gonzalez did become the first man to score against the Reds this summer.
The Reds took the lead as Aspas' delicate chip came back off the bar and an attempted clearing header only went as far as Alberto who hit a crisp volley into the bottom corner.
But the lead lasted just four minutes as Gonzalez got across Jordan Henderson on the edge of the six-yard box and headed home.
Brendan Rodgers' side were back in the lead a minute before the break as Stewart Downing hit the byline and threaded the ball to Aspas in the box who netted his fourth goal of pre-season.
And the lead was doubled nine minutes into the second half as Kelly found the net with the faintest of touches after a corner had caused confusion in the home penalty area.
The victory was sealed when Sterling finished off a slick move involving Philippe Coutinho and Oussama Assaidi.
Adam Johnson scored the only goal as Sunderland closed their pre-season campaign with a 1-0 win over FC Midtjylland in Denmark.
Marco Larsen brought an early save from Keiren Westwood but it took Johnson just six minutes to give the Black Cats the lead.
The former Manchester City man gathered a pass from Jozy Altidore and fired past goalkeeper Jonas Lossl from the edge of the box.
Frank Kristensen almost had the hosts level midway through the first half but Westwood did well to save his close-range header.
Emanuele Giaccherini brought a save from Lossl as half time approached but Pione Sisto almost had the hosts ahead just after the break as Westwood was forced into a low save.
A host of substitutions followed with Midtjylland changing their entire XI but it was Stephane Sessegnon who came closest to scoring again as he hit the bar with seven minutes remaining.