Manchester City's injury crisis has rubbished the lazy stereotype that they have enough resources to field two quality teams at once. Yet on Saturday the reserve team huffed and puffed their way to an FA Cup quarter-final place to teach Pep Guardiola plenty about which players should be part of his future plans.
Most eyes were on Kevin De Bruyne and Ilkay Gundogan, who are arguably playing their way out of contracts, albeit Gundogan is 'close' to triggering an extra year according to Guardiola. Bernardo Silva and Jack Grealish could have done with performances vs Plymouth given Guardiola backed both to be part of his plans for next season.
There were moments of promise and frustration for each of those established names in a game that was made tougher than it needed to be. But the man to bail them out was not one of the leadership group or a treble winner.
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It was the often-forgotten Nico O'Reilly.
The attacking midfielder surprised Guardiola as a makeshift defensive midfielder on tour in the summer before moving back to left-back in the Carabao Cup and staying there in his future cup cameos. In recent weeks he has been Josko Gvardiol's understudy with a front row seat to City's rollercoaster of a season.
"He is not a typical player for the academy, because they are all small," said Guardiola after the game. "He has a big presence. Normally is an attacking midfielder, no.10, arrives in the box and has a sense of goal. But for the problems we have he adapts really well as a full-back. And I think he can play holding midfielder."
His goal against Salford in round three was a first competitive senior goal after his strike against Barcelona in pre-season. His senior tally tripled on Saturday with a brace to bail out his older colleagues.
When he glanced in De Bruyne's cross on the stroke of half-time, he knew better than to celebrate the equaliser and simply gestured to get back to halfway. His teammates will have welcomed a team talk that had just got a whole lot easier.
"He is another threat for set pieces, we're not a tall team and he helps us," Guardiola continued. "He played really good with the ball and without the ball and helped us with two fantastic goals."
His second goal, a dominant header at the back post, earned a proper reaction. O'Reilly slid into the corner, Erling Haaland booted the ball into the stands and every City player and substitute ran towards the goalscorer. He later earned a deserved round of applause when named Player of the Match, allowing a wry smile before continuing.
The celebrations were notable for how many players got involved. It felt like there was plenty of love for O'Reilly as well as celebrating an important goal.
With Gvardiol the best of an inconsistent bunch in defence this season, and new boy Nico Gonzalez more likely to get minutes in midfield, O'Reilly may have to bide his time for regular football and the FA Cup may be his best route - even if Guardiola will probably take fewer selection risks the closer City are to the final.
All O'Reilly can do is show his quality when he does play. He's done that in the cup this season and has a useful knack of scoring important goals when he plays.
"I am really pleased for the game he played and he can help us a lot," Guardiola said in a final offer of future minutes for O'Reilly. With Nathan Ake now struck down again by the centre-back curse and Guardiola joking that O'Reilly scores goals like Gvardiol, perhaps he can offer the left-back cover Ake can't for the end of the season.
That is a situation nobody at City, let alone O'Reilly, will have considered this time last year when he was scoring scorpion kicks as a striker in the academy. It seems City's Swiss Army Knife could have a role to play across the pitch in Guardiola's future plans.
