Mikel Artetaâs side ground out a hard-fought victory against Rapid Vienna last week, but have since suffered a dispiriting 1-0 defeat by Leicester in the Premier League.
Irish side Dundalk, meanwhile, lost 2-1 to Molde in their opening group stage fixture.
Arteta may take the chance to rotate his squad, with academy graduates Reiss Nelson, Emile Smith Rowe and Joe Willock all in contention to feature.
Hereâs everything you need to know ahead of the match.
When is the match?
The game kicks off at 8pm on Thursday 29 October.
Where can I watch it?
The match will be shown live on BT Sport 2. Subscribers can also stream the match via the BT Sport website or app.
What is the team news?
Runar Alex Runarsson could be making his Arsenal debut in goal on Thursday night. With David Luiz out injured, Shkodran Mustafi should be returning for his first start of the season. Cedric Soares, Mohamed Elneny, Reiss Nelson and Joe Willock are all in contention to make outings on the starting line-up.
As Dundalk have suffered two defeats in their matches against Molde and Waterford last week, Filippo Giovagnoli will have to get his squad in shape ahead of the trip against the 2019 runners-up.
Confirmed line ups
Arsenal XI: Runarsson, Cedric, Mustafi, Kolasinac, Maitland-Niles, Willock, Elneny, Xhaka, Pepe, Nketiah, Nelson.
Dundalk XI: Rogers, Gartland, Boyle, Cleary, Mountney, Murray, Shields, McEleney, Dummigan, Hoban, Duffy.
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