Arsenal played with 10 men for over an hour, but were able to withstand pressure from Liverpool to claim a goalless draw in the first leg of the teams' Carabao Cup semi-finals.
The crucial moment of the game came in the 24th minute, when Arsenal's Granit Zaka was sent off to deny Diogo Jota a clear goal-scoring opportunity with a high foot that slid Liverpool forward outside the Arsenal penalty area.
The incident necessitated a switch in Arsenal strategy to a three-man defense, with Mikel Arteta bringing on Rob Holding for Eddie Neketia. It was the second opening change for the away side after Callum Chambers replaced the injured Cedric Soares in the 11th minute.
But when Liverpool later dominated the field and possession, they could not register a shot on goal through Curtis Jones until the second minute of second-half stoppage time.
His best chance came moments earlier, but Takumi Minamino shone from 10 yards after the fall of a weak punch from Aaron Ramsdale.
Minamino first went close twice from the left, first with a mishit cross that went narrowly wide after half-time and then, in the middle of the second period, via a cross-shot that cooped up Anfield's end. But the post was crossed.
Arsenal struggled to create goalscoring opportunities, but came close in the 72nd minute; After being found by a cross from Kieran Tierney from left side, Bukayo Saka saved a shot by advancing Liverpool goalkeeper Alisson.
"We revel against the situation," Arsenal manager Mikel Arteta told Sky Sports. "The players showed great fighting, determination, camaraderie. You saw the spirit, we never gave up. Credits to the boys.
"I don't know whether the red card inspired them or not, but it took a fight. You need a certain attitude to play these games and the boys did it. We played the game we had to play, which was ours. Not playing. I haven't seen it back, they checked it so maybe a red card."
The Anfield meeting was originally meant for the second leg of the semi-finals, but the venues flipped when Liverpool's meeting was postponed last week due to the coronavirus outbreak.
And both teams were missing several key players on Thursday for reasons related to COVID - Arsenal announced ahead of kickoff that Martin Odegaard had tested positive - as well as injury and Africa Cup of Nations commitments.
Liverpool manager Jurgen Klopp told Sky Sports: "We would have preferred to score a goal rather than get him a red card." From that moment it seems we are under pressure [to score] and we had to change the line - for obvious reasons [before the game].
"In the second half we made some changes, I thought it looked better and we had clear conditions but it wasn't good enough. But it's a two-legged game and it's half time. I don't remember when it was." Was 0-0 at half time, wherever I've been, and I thought 'we have no chance'. We'll just let it go."
The second leg will take place on January 20 at Emirates Stadium The winner of the tie will face Chelsea in the final on 27 February.