Jurgen Klopp has been left with plenty to ponder after watching his side get blown away by Brendan Rodgers' side.
Liverpool offered Anfield a glimpse of a bright post-Luis Suarez era with a comprehensive 4-0 win over Borussia Dortmund on Sunday.
Early strikes from Daniel Sturridge and newcomer Dejan Lovren, along with goals from the outstanding Philippe Coutinho and Jordan Henderson after the break, gave the Premier League's runner-up an easy victory over its below-par Bundesliga counterpart.
But it is the performances of a new-look front three of Sturridge, Coutinho and Raheem Sterling that will have given Liverpool boss Brendan Rodgers most satisfaction following Suarez's big-money move to Barcelona.
Exhibiting pace, technique and relentless movement, the trio terrorized Dortmund throughout — and Rodgers' pleasure at their display is likely to be in sharp contrast to the feelings of Ronald Koeman, who brings Southampton to Anfield for its Premier League opener next Sunday.
It took just 10 minutes for Sturridge to open the scoring, as he latched onto a superb Coutinho flick before sliding the ball past Dortmund goalkeeper Mitchell Langerak with the outside of his left foot.
Lovren added a second just four minutes later, as he met an inswinging Steven Gerrard corner with a firm header from 6 yards.
Coutinho fittingly got on the score sheet just three minutes after the interval, as he shot coolly beyond Langerak from close range after being fed by Sterling.
Liverpool saved the best for last, though, with a dazzling piece of interplay between the front three ending with Henderson tapping home.
With a DFL Supercup meeting against Bayern Munich — and former hero Robert Lewandowski — just three days away, Dortmund's abject performance will be of concern to coach Jurgen Klopp.
The lackluster visitors failed to heed an early warning of Coutinho slicing them open with a ball to Sterling, and were punished when Sturridge broke the deadlock.
Lovren fizzed a pass into Coutinho, who produced a wonderful flick around the corner to Sturridge and the striker displayed typical composure to put Liverpool ahead with an ice-cool finish.
Lovren ensured it was a debut to remember shortly after with his first goal for the club, and Gerrard went close on the stroke of halftime as Langerak produced a fine stop to deny his top-corner-bound 25-yard free kick.
Rodgers' men picked up where they left off after the break, with Coutinho deservedly getting in on the act before Henderson rounded off the game's best passage of play with a simple finish on the hour.
Liverpool continued to threaten with Javier Manquillo — another defensive debutant — impressing at right back, while Dortmund toiled.
Coutinho was withdrawn to a standing ovation with 20 minutes remaining of a game that suggested Liverpool is dealing better with the departure of its star striker than a Lewandowski-less Dortmund.