Real Madrid are firm favourites to progress to the Champions League semi-finals after a thoroughly deserved 3-1 win against Liverpool, who require another second-leg comeback at Anfield to keep their European hopes alive.
Here, the PA news agency examines the key talking points ahead of Wednesday night's showdown.
The Reds are the comeback kings
This is not the first time Liverpool have found themselves in this position. Only two years ago, Jurgen Klopp's team stunned Madrid's rivals Barcelona en route to lifting the trophy. Trailing 3-0 from the first leg at the Nou Camp, Liverpool mounted an astonishing recovery at Anfield to win 4-0 and go through to the final.
Wednesday's match also takes place exactly five years to the day since the Reds beat Klopp's former side Borussia Dortmund in the Europa League quarter-finals having been 4-2 down on aggregate with 24 minutes to go and the Germans having scored three away goals at Anfield. Not to mention the 2005 final when Rafa Benitez's Liverpool came from 3-0 down at half-time to beat AC Milan on penalties.
Liverpool must get the basics right
From the first minute at the Alfredo Di Stefano Stadium last week, Klopp's team were sloppy and made woeful errors on and off the ball. Possession was easily surrendered, headers were mistimed, tackles were missed entirely. Trent Alexander-Arnold made a big mistake for Madrid's second goal shortly before half-time, but that was his fourth or fifth misjudgement of the night.
Liverpool's usual high press was rarely seen and with no pressure on the ball and open space to operate in, it allowed Toni Kroos to run the game in midfield. The Reds created their own problems in Spain and, but for a short spell after half-time in which Mohamed Salah pulled a goal back, never got going.
Madrid midfield as good as ever
Los Blancos began the first leg with the same midfield trio as in the 2018 final: Luka Modric, Casemiro and Kroos. With Modric now 35 and out of contract in the summer, we may be witnessing the final chapter of one of the great midfield line-ups of the last decade – or even the 21st century. The 2018 Ballon d'Or winner and his Brazilian and German colleagues proved last week their partnership remains arguably the best in the business.
Modric and Kroos each assisted a goal for Vinicius Junior, with Kroos controlling the tempo of the match with his array of passing, while Casemiro's defensive nous gave a makeshift central defensive pairing of Eder Militao and Nacho the protection they needed – limiting Liverpool to just seven shots, only one of which was on target.
Vinicius confidence high heading to Anfield
The first leg was definitely Vinicius' night. The 20-year-old attacker was such a key part of Zinedine Zidane's gameplan and he produced one of the best performances of his young career. However, it was not just the two goals he scored, his overall play and dribbling were on point too.
After such a landmark night for the youngster, it begs the question where he could go from here. Many of those who have gone on to be great players have had stand-out performances and coming-of-age displays in the Champions League, and this tie may turn out to be one for Vinicius.