Mikel Arteta hands a debut to goalkeeper Alex Runarsson, while Reiss Nelson gets a rare start. The Gunners have some of their big hitters on the bench, as well as exciting teenage striker Folarin Balogun who will be looking to make his debut.
Dundalk XI: Rogers, Gartland, Boyle, Cleary, Mountney, Murray, Shields, McEleney, Dummigan, Hoban, Duffy.
Subs: McCarey, Corcoran, Gannon, Hoare, Flores, Sloggett, Leahy, Oduwa, Colovic, Kelly, McMillan.
Arsenal XI: Runarsson, Cedric, Mustafi, Kolasinac, Maitland-Niles, Willock, Elneny, Xhaka, Pepe, Nketiah, Nelson.
Subs: Leno, Hein, Bellerin, Tierney, Gabriel, Saka, Ceballos, Lacazette, Willian, Aubameyang, Partey, Balogun.
Arsenal came from behind to win their opening match against Rapid Vienna last week, but suffered a demoralising home defeat to Leicester on Sunday. Dundalk are looking to avoid a third straight defeat in all competitions.
Tonight is Arsenal's first ever UEFA clash against an Irish side. Dundalk's last European match against English opposition was back in 1982 against Liverpool. It's a historic night for the visitors, who have done well to reach the group stage. It's a shame there will be no Irish supporters in the stadium.
Hello and welcome to our coverage of tonight's Europa League Group B clash between Arsenal and Irish minnows Dundalk.
KICK OFF: We're underway at the Emirates!
Save! he ball barely leaves the Dundalk half in the opening three minutes as Arsenal look a side fresher than they might given the number of changes made, but when the visitors do attack, Duffy's ball inside finds an unmarked Shields, whose long-ranger needs tipping wide by Runarsson for an early corner.
Arsenal get back to their early pressure and patient build-up, focusing plenty of it down the right flank, and get the ball into the box towards Nketiah, who throws himself to the ground after very little contact from Boyle.
Cedric is seeing plenty of the ball in the Dundalk third with Arsenal pushing their wing-backs on, and when Pepe's low cross is blocked he is first to the loose ball, and should probably do better with so long to see it but smacks it over from 20 yards.
Some lovely one-touch stuff on the edge of the Dundalk box gets Willock into the area, and from a tight angle his low cross into the six-yard box is blocked behind by captain Shields for Arsenal's first corner. Pepe takes the set-piece but he hits it directly into the side netting. Shocking corner.
Willock again finds space on the right of the box after an untracked run, but his low cross is heading straight out before Nelson gets a foot on it on the byline. He looks back towards Nketiah, with Gartland's tackle taking it behind for a corner which is easily dealt with by the visitors.
Chance! It's Kolasinac again getting forward from centre-back into the left flank, and again looking into the middle, and this time seeking out Pepe's run. The Ivory Coast forward sends a header over from 12 yards.
Wide! The Gunners go close again - this time Elneny tees up Nelson to shoot wide of the near post from 20 yards
A rare Dundalk attack doesn't go wasted. It's kept alive on the far side is kept alive by McEleney who wins a corner. Murray takes and gives Runarsson some catching practice.
It's only taken 34 minutes, but Arsenal have had a shot on target. Willock's nice run and cross picks out Kolasinac at the far post, and while his header is catchable for Rogers, he's taking no chances and scoops it over for a corner.
Block! Dundalk struggle to clear their lines with Boyle again coming to the rescue to block WIllock's close-range effort after Cedric fizzes it back into the six-yard box.
Chance! That should be the opener. The ball's left bouncing around in the box after a corner is cleared, with Pepe taking aim from the edge of the box. It falls for Nketiah who looks likely to tap home the rebound after Gartland's block but misses the target by a yard or so.
Over! Elneny, getting all sorts of attention from McEleney as he goes to shoot, spoons well over the bar from distance.
GOAL! Nketiah opens the scoring. It's taken a real howler from the Dundalk goalkeeper to hand Arsenal the breakthrough, as he comes to punch Nelson's corner but gets nothing on it, leaving Nketiah to tap home from close-range for an easy opener.
GOAL! Arsenal double their lead! Nketiah turns inside from the right to Pepe, whose blocked shot turns into a perfect pass for Willock on the left of the box. He takes it down brilliantly with one touch and fires high past Rogers with a second. Game over?
There will be one minute of stoppage time at the end of the half.
GOAL! Roughly 30 seconds into the second half and Arsenal score! Nelson's pass reaches Pepe, he smashes his shot from 20 yards to leave Rogers with no chance. Game over. Pepe needed that, he had a very poor first half.
Substitution: Dundalk make the first change of the game. Sloggett comes on for ex-Watford man Murray.
SECOND HALF: We're back underway for the second half. There's a change to report on from the visitors.
HALF TIME: It wasn't pretty from the Gunners but they go into the break with a 2-0 lead.
McEleney down and needing treatment. Elneny sportingly kicks the ball out of play. Not sure McEleney will be able to continue.
Substitution: McEleney's night ends in injury and he's going to be replaced by Flores. Dundalk make another change while they're at it. Hoare on for Cleary.
Wide! Nketiah tees himself up from the edge of the box with a shot that flashes past Rogers' post.
Substitution: Time for a change in shape. Pepe and Mustafi trudge off, with Willian and Ceballos on in their place. Kolasinac is over to left-back, with Ceballos in midfield in what will surely be a straight 4-3-3.
Arsenal have continued to knock on the Dundalk door in the last few minutes - but aren't finding a way through. It's become a bit of a training match since the third goal.
Substitution: Dundalk make another change. Colovic is on for Duffy.
Substitution: Another double change for the Gunners. It's a first-team debut for Folarin Balogun who is on in place of Nketiah. Balogun was linked with a move away from Arsenal in the summer so this is quite a big moment. The other change sees Kieran Tierney come on for Tierney.
It's Hoban who takes, and knows better than I do that it's a good chance to strike, clearly, but misses Runarsson's bar by a couple of yards.
Arsenal make headway again with Nelson driving well from midfield and finding Willian on the flank. He looks to Balogun in the box but he can't find a shooting position.
More good stuff from Nelson makes space in the box, before a smart backheel finds Tierney in space but he smashes it over.
Wide! Now Nelson drives at the heart of the Dundalk defence before curling a strike wide of the far post.
Block! The ball drops to Tierney, who makes a good connection with the ball. He strikes it goal wards but Gartland makes a good block.
There will be three minutes of added time.
FULL TIME: It's a comfortable victory for Arsenal. Dundalk defended well in the early stages of the game but the floodgates opened late in the first half. The second half was more like a training exercise ahead of Sunday's clash at Old Trafford. Arsenal 3-0 Dundalk.