Liverpool got their last-16 tie with Atletico Madrid off to the worst possible start.
The Reds conceded after just four minutes, the hosts' set piece bouncing off Fabinho's foot in the box and finding its way into the path of Saul Niguez.
It was the first time the Premier League pace-setters have conceded in all competitions in 380 minutes.
They then fell victim to a Diego Simeone masterclass as they failed to register a single shot on target, stifled completely by the Rojiblancos.
In a worrying omen, Atletico have never lost a game when Saul has scored - boasting a record of 32 wins and four draws.
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For the defensively minded, the way Atleti played the game out after taking the lead was thoroughly impressive - even if it came courtesy of some dubious tactics.
Sadio Mane was engaged in a constant tussle with Šime Vrsaljko, while on the other side of the pitch, Renan Lodi did his best to get Mo Salah booked.
Simeone's instructions won't have been to everyone's tastes but they could well be vindicated if his side shock the current holders over two legs and advance to the quarter-finals.
There is a long way to go, however, as Andy Robertson was keen to point out in his post-match interview with BT Sport.
The Scotsman accused the La Liga outfit of profiting from a corner when Liverpool should have had the throw-in in the build-up, "celebrating like they won the tie after the game" and "falling over".
To be fair, Liverpool players have probably forgotten what losing feels like having not tasted defeat in the Premier League for over a year.
Yet this was an unhappy return to the Wanda Metropolitano, where the European champions claimed their title against Spurs on June 1.
Joe Gomez was the only player starting tonight who wasn't in Jurgen Klopp's XI in the final.
The tie is indeed far from over but Liverpool fans will love to see their players so riled and ready to avenge their defeat on Merseyside next month.News Now - Sport News