It was Alex Oxlade-Chamberlain's old boss who spoke of never giving up on people. But Arsene Wenger was talking about Jack Wilshere. 'The Ox' was sold to Liverpool, where the spark of a once promising career flared back to life on a day when his new club were meant to be mourning Philippe Coutinho.
Liverpool's coffee table book of great Anfield days acquired a fresh page with this nerve-fraying 4-3 beating of the league's best team, who arrived with a 15-point lead while the hosts were agonising over Coutinho's January sale to Barcelona for £145m (€163m).
Was that Catalonian talent-grab, which followed Luis Suarez's move to the Camp Nou, further evidence that Liverpool's ability to hang on to world-class players expired with the rise of Europe's superpowers?
If losing your most gifted player is a sign of weakness, a harbinger of doom, Liverpool did a hell of a good job of hiding it with a ball-hounding plan that knocked Manchester City out of their usual rhythm, until a late fightback made local stomachs spin.
With Oxlade-Chamberlain, Roberto Firmino, Sadio Mane and Mo Salah all scoring, the loss of Coutinho was made to seem a mere detail on the payroll, though there will still be times when Liverpool miss his talent for the unexpected.
On a perishing day, they inflicted a first league defeat of the season on City without a £145m (€163) playmaker (sold) and their £75m (€84m) centre-back Virgil van Dijk, who had a minor hamstring injury.
To pretend the Coutinho hole has already been filled might seem a bit glib, but for one day at least time moved on quickly, and Liverpool showed their potential to move in the same direction as City with a dynamic, high-pressing game supported by decisive finishing.
A wake turned into a rave, with Liverpool fans spilling into the gangways as their team went on what Oxlade-Chamberlain called "a bit of a rampage" with three goals in nine minutes.
A freezing afternoon turned red hot with the disbelieving happiness of the home fans. Of all the people to start the deluge - to announce Liverpool's intent - Oxlade-Chamberlain would not have featured in many predictions when his Arsenal career fizzled out and he took a reported pay cut to freshen up his life on Merseyside.
When he motored north to Anfield, it was said Liverpool had paid £40m (€45m) for an enigma with no best position; a player who spoke of wanting to play through the middle without having earned the right to do so.
A reluctant right-winger who ran up too many dead ends and scored too infrequently, Oxlade-Chamberlain started his Liverpool career quietly and it was hard to believe he would emerge transformed. Klopp described him on purchase day as "a player that is positive and willing to take risks to try and make positive things happen". To many, this sounded like a nice way to say he had impressed in the interview and was worth a punt.
In recent weeks, though, he has taken his shot at redemption and his goal against City came from the area where he insisted he was strongest: through the centre. Seizing on a loose ball, Oxlade-Chamberlain drove into the inside-right channel and crashed a shot to Ederson's right.
This declaration of intent was followed by his team-mates as a template for disrupting Pep Guardiola's symphony orchestra.
"Defend them all over the pitch," was Oxlade-Chamberlain's description of Klopp's instruction.
Once again, though, Liverpool's defending could not match their attacking, with Joe Gomez twice losing one-on-ones with Leroy Sane for City's first-half equaliser, and Dejan Lovren misjudging a cross for Ilkay Gundogan to narrow Liverpool's lead.
With the amount of pressure City apply, all defences are liable to crack in a 90-minute spell, so maybe the caveats are unfair. At a minimum, they reaffirm how important Van Dijk will be as Liverpool try to progress from an often-good side with hopes of finishing fourth to title contenders.
The ambition and tenacity displayed by Klopp's side vindicated the manager's willingness to let Coutinho go, or at least not stand in his way.
It was the best possible riposte. It was built on strength of purpose as well as exuberant counter-attacking and cool finishing. The Naby Keita arrival date saga has become a bit wearing, but at least Liverpool know he will be here by summer to provide more speed and ingenuity in midfield (Adam Lallana is also fit again).
A top goalkeeper and perhaps a Champions League-calibre holding midfielder would also enhance their prospects.
But 'tomorrow' was a far-off place in the enthralling 'now' of a win over City, so soon after the 'yesterday' of Philippe Coutinho: a 'now' Oxlade-Chamberlain always seemed to be travelling to without ever quite arriving.