Arsenal were beaten properly on the south coast, and Mikel Arteta did not try to dress it up. Brighton were sharper, more aggressive and far more secure in the basics. Arsenal, by contrast, looked loose, hesitant and strangely fragile in the very areas that usually keep them stable.

This was not a game decided by one moment or one refereeing call or one freak passage of play. Arsenal lost too many duels, gave up too many second balls and made too many bad decisions in possession. At Premier League level, that is enough to get you beaten. Comfortably.

Arteta’s verdict was direct. “Extremely disappointed, but first of all, I think we have to congratulate Brighton for the victory. I think they deserve it, I think they were the better team. And from our side there were certain basics that you need to accomplish in football, especially in the Premier League that we were very far from. In the first duel, the second ball, that put the game, especially how direct they were, in a really difficult place for us.”

That gets to the heart of it. Arsenal were not beaten because of some grand tactical mystery. They were beaten because Brighton won the ugly part of the game and then exploited the technical sloppiness that followed. Once Arsenal started losing first contacts and then coughed the ball up when they did recover it, the match tilted hard in Brighton’s favour.

Arteta made clear that the issue went beyond effort alone. He pointed to repeated technical errors in Arsenal’s own half, and a failure to follow simple principles when trying to play out of pressure. “On top of that, when we did regain the ball, especially in our own half, the amount of technical errors that we did and we didn’t respect any principle of play that you have to get out of those man-to-man situations, that put us always in the back foot, so it was very difficult to control the game.”

That is the damning part. You can accept losing duels against an opponent who is flying. What is harder to accept is compounding the problem with poor execution on the ball. Brighton pressed, Arsenal wobbled, and then Arsenal helped Brighton along by making the wrong choices under pressure. It became a cycle.

Arteta did admit there were moments when Arsenal managed to impose themselves. The trouble was they wasted them. “When we had moments of dominance and control, then we opened them up, but we didn’t finish those actions with the quality that is required to compensate all the other things that you have done. So at the end of the day, I think they deserve to win the game and it’s a big lesson for us.”

That word, lesson, came up more than once. Managers use it when they know the evidence is too obvious to ignore.