William Saliba and Jurrien Timber both scored from corners for the Gunners as they won 2-0 last night.
Amorim said afterwards: “We already knew that it would be a tough game. I think the corners changed the game, the set-pieces. Then we lost the momentum, we tried everything then to control the game again.
"You feel it in the first half, in the environment of the stadium, that we were causing problems. We need to improve in a lot of areas of our game, but we were controlling the game.”
“They are very good because they have a lot of time working on that. Especially on that, they have big players for that, so it is a strategy, and we had two weeks to work on that.
"We tried to do it but we know every team in the Premier League is suffering with set-pieces. It was a shame because we were not playing very well but also Arsenal was not playing very well.”
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