Mamadou Sakho's unconventional style made it a challenge for onlookers to determine whether he was suffering from the effects of concussion or whether it was service as usual.
Having clashed skulls with his Liverpool team-mate Emre Can when trying to meet the same header, his substitution was necessary because he did not appear capable of grasping where he was: that a final was going on around him.
The central defender tried to continue only for Sergio Aguero to turn him easily, forcing Simon Mignolet into the save of the first half and with that, Jürgen Klopp, the Liverpool manager, chose to make the change.
Sakho attempted to convince his manager that he was alright by twitching the muscles in his neck and spraying liquid over his face but Klopp's mind was settled and the Parisian's name was already being beamed across Wembley's giant screens.
Sakho's anguish from there was so raw and audible he almost achieved the improbable feat of reaching a greater volume than the stadium's notorious public address system: hurling a water bottle towards the substitutes' bench, he trudged to his seat where he remained for the next 10 minutes wearing a tracksuit top over his head, attempting to cover the visual proof of pain.
Liverpool would have to try and win the cup against Manchester City with Kolo Touré and Lucas Leiva as centre-halves, and for the last 20 minutes at least, with James Milner at left-back. By then Alberto Moreno, on a booking, had made so many mistakes that he could not be trusted to carry on. Lucas was Liverpool's best player, his defiance a feature of the narrative from the instant he soared highest to head clear a Bacary Sagna cross through the zone of uncertainty between goalkeeper in defence in the opening five minutes. Yet he also missed a penalty in the shoot out.
The Brazilian could not have had too many visions during a childhood spent in Porto Alegre where he was regarded as a box-to-box midfielder, of anchoring Liverpool's defence in a game of such importance. It was Klopp's boldest selection since arriving at Liverpool five months ago.
Liverpool recovered from Fernandinho's opener to equalise. Fortune, initially, was involved. There will be jokes about Raheem Sterling having his best game for his former club. He missed two glaring opportunities to secure the outcome in City's favour before surrendering possession in the seconds before Philippe Coutinho took the game to extra time.
City's midfield was unimpressive and they could not supply Aguero with enough possession. Yet Liverpool, despite their numerical advantage in the area after Fernando was withdrawn, possessed neither the acceleration to break quickly enough, nor the variance in passing range to penetrate City's vulnerable defence.
Throughout Friday and into Saturday, Linda Pizzuti, the wife of Liverpool's principal owner John W. Henry released a series of photographs on social media of the pair taking in some of London's classic sights: Churchill's war rooms in Whitehall being the first before they moved on to the Tate Modern art gallery. In Sunday's small hours, there was another one: this of Henry and chairman Tom Werner engrossed in conversation with Klopp at the team hotel before a table of Italian lager.
The images simultaneously acted as a reminder that the key decision makers from Fenway Sports Group are not based on Merseyside and that in their absence, many key decisions have not been the correct ones.
It was telling that of the Liverpool team that started here against Cardiff City the last time they lifted the League Cup, only Jordan Henderson remained from the side and that was four years ago. When FSG became owners of Liverpool they preached the importance of buying them young and building from there.
Sterling may have endured a torrid performance against his former employers but he travels back to Manchester as a victor, vindicated by his decision to push through a controversial move which meant Liverpool lost a talented player.
Liverpool reached a penalty shoot out with a centre midfielder in defence, a right winger at left back and their high profile summer signing in Christian Benteke long resigned to his fate of spending the day on the substitutes' bench. Klopp says he does not need to sign a minimum of seven players like Liverpool have done in the last two summers. But he might need to go close.