Arsene Wenger has praised his side's "mature and intelligent" performance in their Premier League win over Newcastle United at St James' Park.
The Gunners faced 10 men for most of the match after Aleksandar Mitrovic was sent off early on, before a Fabricio Coloccini own goal handed the visitors the 1-0 win.
The manager told BT Sport: "We were always on top. We were mature and intelligent and the win was important so maybe we were a bit cautious. They toughened the game up, they decided from the start to make it very physical but we kept our nerve.
"We are out there and working on [signings]. I am optimistic but it is difficult to predict. We have offensive potential but you always want more and more goalscorers. We have not fired offensively, our finishing has not been clinical and have to improve on that."
The result leaves Arsenal with seven points from their first four fixtures of the new season.
