Arsenal goalkeeper Kepa already had a tortured relationship with the Carabao Cup and the Spaniard's latest mishap in the tournament's showpiece proved decisive.

Allowing Rayan Cherki's cross to slip through his fingers, Kepa presented O'Reilly with the chance to put City ahead in the second half.

O'Reilly struck again just four minutes later to seal City's ninth Carabao Cup, giving boss Pep Guardiola a record fifth triumph in the competition.

Mikel Arteta chose to ignore Kepa's Carabao Cup history when he selected the former Chelsea keeper instead of first-choice David Raya, but the gamble backfired spectacularly.

Playing for Chelsea in the 2019 final, he infamously refused to be substituted just before the shoot-out, then failed to save a single kick, while in the 2022 defeat against Liverpool he missed a penalty in a shoot-out.

Arsenal's failure to win the first trophy since the 2020 FA Cup was a painful blow, ending their bid to land an unprecedented quadruple.

They paid the price for Arteta's unnecessarily conservative tactics, but the season is far from over for the north Londoners.

They remain firmly in control of their bid for a first English title since 2004, while also facing Southampton in the FA Cup quarter-finals and Sporting Lisbon in the Champions League quarter-finals.

After failing to win silverware last season and falling well behind Arsenal in this season's Premier League title race, this was a vital success for City, coming just days after their Champions League last-16 exit against Real Madrid.

Guardiola has yet to confirm whether he will remain at City next season after another season of speculation that this could be his latest campaign in Manchester.

But the Spaniard's frenzied celebration of his 15th major trophy at City suggested his passion is undimmed.

Now Guardiola can focus on using City's first win over Arsenal since 2023 as a springboard to close the nine-point gap on the Premier League leaders.

- City power surge -

James Trafford started in goal for City instead of regular first-choice Gianluigi Donnarumma and the understudy quickly repaid Guardiola's faith with a sensational triple save.

Kai Havertz was presented with a golden opportunity by Martin Zubimendi's deft pass.

But Trafford spread himself to block the German's close-range shot before using his chest and then his out-stretched foot to twice deny Bukayo Saka from the rebound.

Arsenal stifled City with their well-drilled pressing but showed little creativity after that initial burst.

Even the Gunners' trademark dominance at set-pieces was absent and City fans chanted 'boring, boring Arsenal' after Piero Hincapie nodded over from Saka's corner.

City were transformed in the second half, tormenting Arsenal with a spell of unrelenting pressure.

City were furious when Kepa escaped with a booking after racing out of his area in a misjudged attempt to stop Jeremy Doku reaching Matheus Nunes' long pass.

But Kepa's habit of making costly mistakes wasn't about to fade away and the Spaniard's blunder gifted City the lead on the hour.

The build-up was vintage City as Rodri's lofted pass picked out Bernardo Silva and he fed Cherki for a cross that should have been a routine catch for Kepa.

Instead, he let the ball squirm through his grasp and O'Reilly pounced to head home from close-range.

Shell-shocked Arsenal completely lost their composure after Kepa's blunder and City delivered the knock-out blow four minutes later.

Nunes was the catalyst with a perfectly weighted cross to the far post, where O'Reilly steamed past Saka to bury a clinical header past Kepa.

Guardiola's joy was unconfined as he punched the air and sprinted down the touchline.

Booked for his extravagant celebration, Guardiola was again unable to contain himself when the final whistle signalled the end of City's trophy drought.