The Reds have impressed so far on their pre-season tour and they completed victory thanks to a solid display at the Rajamangala Stadium in hot and humid conditions in Bangkok.
Yet it was the presence of striker Luis Suarez, the subject of continuing speculation over his future after two rejected bids from Arsenal, which will grab most attention.
He was handed a run out for the final 29 minutes and he very nearly got his name on the scoresheet when he struck the crossbar.
The Merseysiders broke the deadlock after 17 minutes as the impressive Coutinho stepped inside his marker before calmly slotting the ball into the far corner.
The hosts threatened to restore parity soon after when striker Teerasil Dangda fired inches wide of Simon Mignolet's goal.
Just minutes into the second half, Liverpool doubled their advantage when 25-year-old summer signing from Celta Vigo Aspas took Coutinho's pass in his stride before sending the ball past the busy Sinthaweechai Hathairattanakool.
Gerrard scored the goal of the night as the skipper completed the scoring thanks to a delicious chip from just inside the area.
Suarez, who has made no secret of his desire to leave the club, was then introduced by manager Brendan Rodgers.
It was his second successive substitute appearance on the tour having linked up with the squad late due to an extended break after the Confederations Cup.
And the Uruguay international almost made an instant impact by heading Gerrard's inswinging cross against the crossbar.
Gerrard, who will celebrate his testimonial at Anfield next weekend, also rattled the woodwork late on while Jordan Henderson had an effort cleared off the line.
Liverpool next take on Olympiacos, Valerenga and Celtic ahead of the new season on August 17.