Welbeck benefited from Pérez’s range of passing in a display that will have enhanced the Spaniard’s chances of adding to his two Premier League starts this season

On some days everything just clicks and you wonder why Arsenal can’t play like this all the time. They hint at having so much in reserve; Arsène Wenger included the defender Rob Holding, the teenage midfielders Jeff Reine-Adélaïde and Ainsley Maitland-Niles, and the winger Lucas Pérez, all second-stringers.

Maitland-Niles showed a precocious spatial awareness and range of passing. Reine-Adélaïde caught the eye with his bursts from midfield and a mature knack for knowing when to surge forward or attempt a killer pass. They are fine prospects, but it was Pérez who made the strongest case for a bigger role.

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Theo Walcott and the returning Danny Welbeck, the other members of the attacking trident, were devastatingly clinical but it was Pérez who was at the heart