When Kevin De Bruyne raced back to intercept a Liverpool attack, stopping their threat but unable to prevent a corner, he slid towards the baying away end in vain.
The visiting fans mocked him as he got to his feet, knowing they will finally end four years of hurt at the hands of Manchester City by getting their hands on the Premier League trophy in the coming weeks or months.
De Bruyne spent a lot of this blockbuster clash chasing lost causes. Sometimes after giving the ball away himself, sometimes when a teammate had given the ball away. At one point he almost took out Pep Guardiola on the touchline trying to keep a ball alive.
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Guardiola later took him off, another premature exit for a player making fewer and fewer impacts on big games for City, if he is selected at all.
If this was the last time we see De Bruyne grace a major Premier League fixture, or even a City-Liverpool clash, then it didn't go the way he would have hoped.
The aim would have been to impact the game like Mohamed Salah did. The Egyptian is in the same situation as De Bruyne in that every time he faces an opponent these days it could be his last for his club. Both talismanic talents are out of contract in the summer, with no guarantee of new deals for different reasons.
De Bruyne, not short of effort or desire, lacked the quality or confidence he used to ooze. His last act of the first half was to spoon a half-volley well wide. And given his struggles to break down Liverpool, De Bruyne's number was first up.
That is another 'big' game where Guardiola has overlooked him or replaced him when he needs a goal. He was on the bench vs Chelsea, hooked at PSG with City at 2-2, benched at Arsenal, overlooked vs Newcastle and Real Madrid away. Now, it was James McAtee replacing him to give City a spark for an unlikely comeback.
The Belgian went off first against Manchester United, too. So either he cannot complete 90 minutes in these intense games, or Guardiola doesn't fully trust him to make the difference any more.
Guardiola insisted this week that De Bruyne can still influence big games for City. He pointed out that started the home game vs Real Madrid but added that De Bruyne didn't have the physicality he wanted at the Bernabeu, which felt damning.
In defending his tactical change against Liverpool, Guardiola said he saw plenty of things that he liked but that they missed the 'magic'.
Speaking to Sky Sports, he said: "I saw many things that this club has a bright future with the players that we have. Except Kevin de Bruyne and maybe Nathan Ake, all the players are so, so young. What the club decides next for the future, there is a bright future for this club in the next years.
"Everyone knows that a part will be here next season for the older players but we have to build for the next step. There is a question of time."
First, Guardiola namechecking De Bruyne and Ake is because they were the two 'veterans' in the line-up against Liverpool. In fact, at an average age of 25.68 this was the joint-youngest line up Guardiola had ever fielded in the Premier League.
But De Bruyne will know how this season is going. Ake will feel Guardiola's comments that players who can't stay injury-free can't stay for the long-term. That was a question in relation to John Stones' latest injury, while the likes of Mateo Kovacic, Ilkay Gundogan and Jack Grealish were overlooked for the younger, more attack-minded starting XI.
Bernardo Silva was, too, although that could have been a fitness call as he stayed on the bench. Kyle Walker is another who is older and looks to have taken it upon himself to leave before being forced out.
If the 90 minutes vs Liverpool exposed how far away City have slipped from title contention, Guardiola will hope to look back on the new system with a youngest-ever team and see the same game as a turning point.
It could also be the end of at least six City careers.
