Liverpool 0-0 Arsenal (4-5 pen)
Despite Liverpool dominating the rhythm of the game, they failed to create any chances of real quality as Arsenal forced the tie to penalties.
The Reds enjoyed decent spells of possession during the opening exchanges. However, Arsenal had the first big chance through Eddie Nketiah, who tried to take the ball around Adrian, but the Reds goalkeeper did well to palm the ball away from goal.
Arsenal were criticised in some quarters for their limited attacking intent during the first half on Monday night, but it was more of the same from Mikel Arteta's side.
The Gunners were content to stick to their shape and defend deep, which frustrated the Reds as they struggled to create any clear-cut chances.
But Liverpool should have made the breakthrough just before half-time as Jota's header forced a good save from Leno. Minamino followed in the rebound but his close-range strike could only crash into the crossbar and bounce away to safety.
The Reds looked far likelier of the two sides to get the crucial opener after the break, with Grujic and Van Dijk going close twice from close-range.
Joe Gomez and Divock Origi came on for the final half-hour, replacing Van Dijk and Salah - the two surprise inclusions in the starting eleven.
Jota had another excellent chance to make it 1-0; forcing Bernd Leno into making a good save after he brought down a long ball and got a powerful strike off from just inside the box, with the Arsenal goalkeeper being kept busy by the Reds forward line.
The visitors had a rare opportunity through a set-piece but were denied through Adrian, who got down well to deny Rob Holding's powerful header.
Jota was withdrawn with 15 minutes left to play as Gini Wijnaldum came on to replace him and make his first appearance in the competition in three years.
Despite the Reds' best efforts, Arsenal did well to keep them at bay as the game went to penalties - just as it did in the cup last year and during August's Community Shield.
James Milner, Wijnaldum and Minamino all converted before Adrian saved Mohamed Elneny's spot-kick to make it 3-2 in the shoot-out.
But Origi squandered Liverpool's advantage as his penalty was saved by Leno, with Ainsley Maitland-Niles levelling the scores.
Jones dispatched his corner into the bottom left before Pepe made it 4-4. But Harry Wilson was denied by Leno as Joe Willock squeezed his penalty through Adrian to seal 5-4 win on penalties.
Liverpool XI: Adrian, N Williams, R Williams, Van Dijk, Milner, Grujic, Jones, Wilson, Salah, Jota, Minamino.
LFC Globe's MOTM: Marko Grujic
Next Fixture: Aston Villa (A) - 1 Oct, 4.15pm
MORE: Highlights →