The Icelandic goalkeeper made his first appearance for the Gunners on Thursday night after joining them in the summer from Dijon for around £1million.
Runarsson had a straightforward night in goal, barely having to make a save as Arsenal cruised to a 3-0 victory.
“I’m proud to have reached this achievement,” said Runarsson, reflecting on his debut. “And I'm proud of the team that we got a very good win.
“All games in Europe are difficult so it is a very good result.
“You have to be alert for maybe the one or two chances [they have] and I was a little lucky it came at the beginning of the game, it gave me a good start. But I think this is going to be the image of a lot of games for Arsenal.
“I think that is normal playing for a club like Arsenal, we have the ball a lot and there are going to be a lot of games like this.”
The victory for Arsenal maintained their 100 per cent record in the Europa League this season and they sit top of Group B.
And asked if the Gunners should view winning the Europa League as a route back into the Champions League, Runarsson said: “Yes, definitely.
“It gives us a lot of experience as a group to get minutes in Europe and it will only help us in the league as well and go on into the future.
“We went into the group as big favourites so we need to aim for that point, but as I said every game is Europe is a tough one.
“We saw that last week against Rapid Vienna, they went up 1-0 and they were so strong. Against Dundalk we decided that we had to get a strong start to the game and 3-0 is a good result.”
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