The Gunners felt they had secured a late winner in an away game against Fulham on Sunday.
However, Bukayo Saka’s header was deemed offside due to Gabriel Martinelli straying in the buildup.
“I haven’t seen a team do what we’ve done here today against them,” the manager said after the 1-1 draw.
“That’s the reality, but you want that and the three points, and that’s what was missing today. We’re going to have to work in that direction and improve those margins.
“We’re very disappointed that we didn’t manage to get the three points, obviously. With the way we dominated the game from the start to the end, and how much the team wanted it, but these are the small margins.
“They have the quality, they had one action to score one goal and we have to dig in to do so much to merit a lot of the stuff that happened in the game on our side. At the end, we find a way to score – it was disallowed - emotionally that was tough.”
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