When Mikel Arteta scanned a well-stocked substitutes’ bench for potential matchwinners, Calum Chambers’ face would not have leapt out. So it was a turnup for the books that his defender, who had not kicked a competitive ball in anger for two months and has barely appeared in a matchday squad since, breached Leeds within seconds of coming on and sparked an ultimately straightforward win. Chambers just about beat Illan Meslier with his first touch and Arsenal’s progression to the quarter-finals was in little doubt thereafter. Chambers had only been deployed because Ben White felt unable to continue after feeling unwell. His intervention was the cue for Arsenal to take complete control of a previously sterile game and their second goal was a reminder of another talent whose career sits at a crossroads. Eddie Nketiah’s only previous football this season had come in the third round of this competition, against AFC Wimbledon; he scored in that game and squeezed in another here, although the path to salvaging a long-term future in north London still appears rocky for a player who needs regular starts at 22. Few people doubt his poaching instinct but Arteta’s post-match comments leaned towards regret that he cannot find a place for Nketiah in his Premier League selection rather than a pledge of future involvement. All the same, an eighth game without defeat spoke well of his fringe men’s willingness to come in from the cold and suggested that Arsenal’s depth, which has come into question, is significantly greater this year. It took several seconds for Chambers’ first goal since September 2019 to be given, but the reaction spoke volumes. Emile Smith Rowe, who joined White in remaining from the Premier League win over Aston Villa, had been relatively subdued but swung over a corner that Nketiah flicked on. Nicolas Pépé nodded back at the far post and an alert Chambers, having run straight into Leeds’ box, saw his header scooped out by Meslier. Eventually Andre Marriner signalled it had crossed the line and sparked an exuberant celebration in front of the technical area. “He totally deserved it,” said Arteta of Chambers, who made a beeline for the set-piece coach Nicolas Jover as he raced towards the touchline. “It was a great moment because he helped us to win the game. He is someone who deserves the best, for how he is as a person and a professional.” There was “something else” to the acclaim Chambers took from his teammates according to Arteta, who implied such a long spell out of the team had been difficult to take. Nketiah’s situation has been similar and his manager was thrilled when, after a woefully undercooked header back from Liam Cooper, the centre-forward nipped in to dink the ball past a stranded Meslier. Even if his subsequent finish was not clean, it did the job; Arteta was keen to stress that is what Nketiah always does. “I have no doubt over what he can offer,” he said. “Whatever you throw at him, he wants more. I’m delighted to see the performance he had. I have full belief he will be a top player, and hopefully at Arsenal.” For that to happen, Nketiah will want at least a few more morsels of action before the quarter-finals in December. He was central to a bright start from Arsenal, who faded after the 20-minute mark and watched Leeds come closest to scoring during the first half. Jack Harrison’s snap shot forced a solid parry from Bernd Leno, another player whose face is decreasing in familiarity, while Tyler Roberts saw a shot deflected wide after Rodrigo’s clever dummy. In bursts Leeds showed a semblance of the vim they have lost this season under Marcelo Bielsa, who made a relatively paltry four changes, but they lost their way after the interval. The game seemed well poised but they never threatened again and perhaps he overthought things in making three early changes. “Clearly the differences between the first and second half came after the goal,” Bielsa said, although he admitted he is “responsible for the effects of the subs”. Leeds’ more pressing concern is a trip to Norwich on Sunday and, in the long run, a full 90 minutes for the returning Kalvin Phillips may prove the most valuable outcome from an otherwise bland night’s work. Arteta will hope White, who had only played because Pablo Mari was suffering from a bug of his own, perks up in time to face Leicester. Martin Ødegaard had also been due to start but picked up a knock. For Arsenal, though, the good news is beginning to override the niggles consistently.