Enzo Maresca admitted Manchester City did not practice penalties at all this season before beating Brighton & Hove Albion in a League Cup fourth round shoot-out on Wednesday.
City goalkeeper Geronimo Rulli made two penalty saves as the League Cup holders won 4-3 in the shoot-out after twice coming from behind in a 2-2 draw at the Etihad Stadium.
Maresca had opted against asking his players to practice penalties in training since his close-season arrival to replace Pep Guardiola.
City's lack of spot-kick preparation was no problem thanks to reserve keeper Rulli, who denied Brighton's Yasin Ayari and Lewis Dunk to send City into the last eight.
Mateo Kovacic did miss from the spot but Phil Foden, Enzo Fernandez, Jeremy Doku and Rayan Cherki were all successful.
"To be honest, since I've been here we never practised penalties," said Maresca, whose side will host third tier Bradford City for a place in the semifinals.
"We're very happy with the five, even Mateo. It always happens, the one that scored during the 90 minutes, and then misses the penalty."
Kovacic had cancelled out Malick Yalcouye's opener for Brighton before halftime.
Georginio Rutter restored the Seagulls' lead after the restart, but Vitor Reis diverted in a Cherki free-kick to take the match to penalties.
"I'm not sure he changed the game, but for sure he made an impact," said Maresca of Belgian winger Doku.
"This is the reason why they are there – when they start from the beginning, to try to do their best, and if they go on from the bench, to try to make an impact."
City had suffered their first Premier League defeat this season on Saturday, losing at Aston Villa to end their 100 per cent start to the top-flight campaign.
It was vital for City to bounce back with a win against Brighton as they try to remain positive while awaiting the verdict in their appeal against a guilty verdict over breaches of Premier League financial rules.
If the appeal fails, City could be hit with a massive points deduction that would effectively lead to relegation.
In the midst of a pressure-packed schedule, Maresca had no regrets about his decision to rest Erling Haaland, Gianluigi Donnarumma, Ruben Dias, Elliot Anderson and Josko Gvardiol against Brighton.
"I was happy with the way we planned the game, with the rotation, and especially I was very, very, very happy with the ones that were playing," he said.
Maresca, who made nine changes, praised Donnarumma's deputy Rulli for his composed display.
"Apart from the penalties, I think overall he was good, especially in the build-up. He also made a good save," he said.