Fifty-one years is a long time to wait for a moment, and for sixteen minutes today, Mansfield Town had theirs. Will Evans's equaliser on 50 minutes silenced whatever travelling support had made the trip, and suddenly Arteta's rotated, reshaped, twice-injured side was staring at the kind of result that follows a club around for decades. The cup giant-killing, the banana skin that everyone had been predicting all week, almost willing into existence.Then Eberechi Eze stepped off the bench and reminded everyone who the Premier League leaders are. His shot from the edge of the area fizzed high into the Mansfield net on 66 minutes and that, ultimately, was that. The dream that Nigel Clough had carefully, respectfully, honestly nurtured all week was extinguished, and we moved on with four competitions still intact.

Mikel Arteta made nine changes from the side that beat Brighton in midweek. The headline name among the changes was Marli Salmon making his full debut in defence at 16 years old. But the player who grabbed the afternoon by the collar and refused to let go was Max Dowman, also 16, making only his second career start.

He was a persistent creative force, able to beat his man on either side, always looking forward, always wanting the ball in the tightest of moments. In a team that spent large portions of the afternoon looking laboured and disconnected, Dowman was the one who looked like he belonged at a higher level than where he was playing.

He missed an early one-on-one with Liam Roberts and had a shot saved directly on the half hour. He nearly restored our lead after Evans had equalised, forcing another Roberts save from a scintillating switch of feet. His runs were also directly behind the goalline clearance Kyle Knoyle had to make to deny Gabriel Jesus.

The frustrating thing is that Dowman was doing most of this while the senior players around him were not pulling their weight. Gabriel Jesus and Gabriel Martinelli had poor afternoons. For long stretches, Dowman was the only Arsenal player genuinely threatening to unlock a League One defence.

Arteta's initial formation deserves honest scrutiny. The 3-1-5-1 he went with, with Christian Norgaard stationed in front of the back three and Dowman, Havertz and Trossard as a fluid central midfield trio, simply did not work. The back three of Salmon, Cristhian Mosquera and Riccardo Calafiori looked out of sync and were frequently exposed. Mansfield's Rhys Oates was getting around Mosquera in the opening exchanges. Louis Reed was testing Kepa on 12 minutes. Tyler Roberts was shooting just off target. The shape was inviting pressure and not providing enough structure to absorb it.

Trossard was forced off injured in the 38th minute, Calafiori followed him to the dressing room for good in the 74th, and in both cases we were fortunate the scoreboard did not punish the disruption more severely. When Arteta brought on Piero Hincapie for Trossard and switched to a 4-3-3, things improved almost immediately, which tells you most of what you need to know about the wisdom of the original system.

Mansfield, to their credit, were physical and direct but not in a mindless way. Clough had promised beforehand that his players would "make it as uncomfortable as possible" for Arsenal, and they delivered exactly that. If there was a forward pass to be played, they played it. If there was a shooting opportunity, they took it. Evans's equaliser was the result of Salmon leaving a back pass short, allowing Evans to nip in, surge up the inside left channel and drive a low finish past Kepa. It was deserved in the context of the half.

It would be wrong to only reach for the negatives. Noni Madueke's goal, which put us ahead just before half time, came in the manner you want from a wide forward. Martinelli worked the ball back to him, and after Roberts kept out his first attempt, Madueke's second shot fizzed high past the goalkeeper from the edge of the area. When Eze came on and did the same thing sixteen minutes after Evans had equalised, it was the work of a player who had been waiting patiently for exactly this kind of moment. Arteta has managed him carefully this season, and the investment paid off the instant the ball hit the top corner.

Mansfield had a half chance through the substitute Oliver Irow in stoppage time, his header too close to Kepa to cause any genuine alarm. We held on, progressing to the quarter-finals.

Arsenal, though, should be feeling something more complicated than simple satisfaction. The squad depth that allowed Arteta to make nine changes and still come through a genuine test is real and should not be understated. But the manner of this win asks questions that a comfortable scoreline might otherwise obscure. The original formation was a mistake that Arteta had to correct at the cost of a substitution. The back three looked raw and vulnerable for long stretches against a side sitting 16th in League One. Two defenders left the pitch injured. The senior forwards, Jesus and Martinelli, had afternoons to forget. And it took a substitute, introduced after the hour, to finally settle a tie that should never have been in the balance.

None of this is cause for panic. This is a squad that is seven points clear at the top of the Premier League with four competitions still live. We have found a way through genuine tests before, and it did so again today. The quality is there. But the questions raised on a difficult pitch in Nottinghamshire deserve honest answers before the stakes get considerably higher. The quarter-finals are booked, the quadruple is intact, and Dowman just reminded everyone why the excitement around him is entirely justified.