Mikel Arteta lamented Arsenal’s lack of purpose, aggression and threat as they slipped to a last-gasp 1-0 defeat at Porto in the first leg of their Champions League last‑16 tie. The Arsenal mana­ger was ­furious at the 94th‑minute con­cession – curled home superbly from long‑range by the Porto winger Galeno – saying his team had failed to manage the situation. Arteta passed unforgiving judgment on the performance as a whole, which derailed the club’s momentum. They had arrived in northern Portugal having won all five of their matches since the winter break. “I am very disappointed with the way we gave the game away at the end,” Arteta said. “Not managing that situation well enough. You get punished in the Champions League. If you cannot win it, you don’t lose it. “We dominated the game but we lacked purpose, especially in the first half. You need to have much more aggression, you need to break lines, to play forward and generate much more threat on that backline. “In the second half there were much better things and we ­generated a lot of situations, without really ­creating much from it. We will learn from it. Now it is clear, it is half time. If you want to be in the quarter-finals you have to beat your opponent.” Arteta was asked whether his team were naive. It was the club’s first appearance in the Champions League knockout rounds since 2017 and most of his players had never played on this stage. “Well, it’s only [on] the last ball,” Arteta said. “So if in 94 minutes they haven’t had any naivety other than that one, I think it’s a bit cruel to judge it. But it’s true that it has had a big impact on the result. A lot of other things they did for the first time here were very good. “Credit to Porto. They defended well. But when we got in certain areas we didn’t finish the action or put in the final ball or the right cross. Even from set pieces, every time we touched somebody it seemed to be a foul before we even kicked the ball. We will learn and do better.”