Liverpool surrendered a two-goal lead for the second-successive game as Monaco came from behind to win 3-2 in a preseason friendly at Anfield.
Alexander Isak and Florian Wirtz put Liverpool in control during an impressive first half, but Aleksandr Golovin pulled one back from the penalty spot before the break and Mika Biereth levelled early in the second half.
Paris Brunner then completed Monaco's comeback with a late header to condemn Andoni Iraola to defeat in his first game in the Anfield dugout.
In their previous preseason game in Chicago, Liverpool let a two-goal lead slip against Leeds United and lost 4-2.
The afternoon began with a minute's applause for Liverpool legend Kevin Keegan before both sides made a lively start.
Monaco threatened inside the opening minute when Biereth got into the box and forced Alisson into a save, before Liverpool quickly began to take control.
Wirtz was denied by Lukas Hradecky after good work from Isak before Cody Gakpo fired wide following a flowing Liverpool move.
Liverpool made their pressure count in the 16th minute when Ryan Gravenberch exchanged passes with Dominik Szoboszlai before finding Isak, who turned and rolled his finish into the bottom corner.
Monaco responded when Aline's deflected effort forced Alisson to tip the ball over the bar, but Liverpool continued to create opportunities and doubled their advantage in the 29th minute.
A cross from Lewis Koumas caused a scramble inside the six-yard box after Gakpo headed the ball back into danger, allowing Wirtz to poke home from close range.
Liverpool appeared in control, but Monaco were handed a route back into the game shortly before half-time when Virgil van Dijk brought down Golovin inside the penalty area.
Golovin stepped up and converted the spot-kick in the 44th minute despite Alisson diving the right way to reduce the deficit to 2-1.
Liverpool made two changes at the break, with Wataru Endo and Giorgi Mamardashvili replacing Alisson and Ndukwe.
Monaco drew level in the 56th minute when Biereth burst into the area and saw his first effort saved by Mamardashvili before reacting quickest to the rebound and finishing at the second attempt.
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Liverpool then made a host of changes on the hour, with Wirtz, Kostas Tsimikas, Isak, Gakpo, Gravenberch and Van Dijk all withdrawn. Victor Muñoz was among those introduced for his first Liverpool appearance.
Midfielder Curtis Jones was left of the squad with speculation around his future at the club continuing to grow.
The changes disrupted Liverpool's momentum and Monaco began to look the more dangerous side. Mamardashvili produced an important save to deny Coulibaly in the 70th minute before Konate dragged another Monaco effort narrowly wide.
Liverpool had made 11 changes by the closing stages and struggled to recreate the attacking fluency of their first-half display.
Monaco completed the turnaround in the 88th minute when Brunner rose at the near post to meet a corner and headed home the winner.
Liverpool next face Como at Anfield on Aug. 16 in their final preseason fixture.