Arsenal maintained their perfect record in this season's Europa League as goals from Eddie Nketiah, Mohamed Elneny, Joe Willock and Folarin Balogun sealed a 4-2 win at Dundalk in their final Group B match on Thursday.
Much-changed Arsenal, who rested several senior players having already qualified for the last 32, went ahead in the 12th minute when Nketiah chipped the ball over Dundalk goalkeeper Gary Rogers for his fifth goal in all competitions this season.
Elneny doubled the lead with a shot from distance six minutes later for his first Arsenal goal in three years, but the Irish side hit back through Jordan Flores who beat Runar Runarsson following a neat exchange with Michael Duffy.
Bottom-placed Dundalk had the opportunity to equalise but Darragh Leahy's effort from point-blank range was blocked by Calum Chambers before Willock struck with a low shot after the interval to make it 3-1 to Arsenal.
Substitute Balogun added a fourth with a side-foot finish after being played in by Nicolas Pepe 10 minutes from time before Sean Hoare nodded in a consolation goal for the hosts at Dublin's Aviva Stadium.
"The group stage in general is really positive. It's never easy to win six games in Europe. We've been really consistent and performing well," Arsenal manager Mikel Arteta told reporters.
Arsenal, who scored 20 goals in the six group games, will discover their last-32 opponents in Monday's draw in Nyon, but Arteta was focusing Sunday's Premier League game against Burnley.
Arsenal are 15th in England's top flight with 13 points from 11 games, three places above Burnley who are in the relegation zone.
In other matches, Real Sociedad and Young Boys squeezed into the last 32 of the Europa League and were joined in the knockout phase by Napoli, Molde, Maccabi Tel-Aviv and Wolfsburg while Tottenham Hotspur secured top spot as group play concluded on Thursday.
Jose Mourinho's Spurs side had already guaranteed progress but second-half goals by Carlos Vinicius and Giovanni Lo Celso earned a 2-0 win over Royal Antwerp as they leapfrogged the Belgians who had also qualified from Group J.
While Tottenham cruised it was a frantic night across the continent as others left it late to stay alive.
Real Sociedad's Willian Jose snatched a stoppage-time goal to secure a 1-1 draw at Napoli as the high-flying Liga side got through in second spot behind the Italians in Group F.
They were in danger of heading out as they trailed to Piotr Zielinski's 35th-minute effort for section leaders Napoli but breathed a sigh of relief with Willian Jose's late leveller.
AZ Alkmaar would have finished above Sociedad with a win at bottom club Rijeka but lost 2-1 as Ivan Tomecak scored for the Croatian hosts in added time to secure their only group win.
For Swiss club Young Boys it was even tighter as they beat visiting Romanians Cluj 2-1 in a dramatic Group A clash.
Cluj, who needed a win to leapfrog Young Boys, went ahead in the 84th minute through Gabriel Debeljuh.
But in an astonishing climax Jean-Pierre Nsame's penalty levelled it in stoppage time after keeper Cristian Balgradean was red-carded before Nsame was himself sent off in the 95th.
A minute later Gianluca Gaudino slotted a Young Boys winner and Cluj ended with nine men as Damjan Dokovic was dismissed.
Young Boys finished runners-up behind already-qualified AS Roma who lost 3-1 at CSKA Sofia.
Norwegians Molde progressed as they drew 2-2 at Rapid Vienna who could have overtaken them. Captain Wolff Eikrem scored twice for Molde who finished second in Group B behind Arsenal as the London side won 4-2 at Dundalk to finish with maximum points.
In Group I Maccabi Tel-Aviv beat Sivasspol 1-0 with an Enric Saborit goal to grab runners-up spot, while in Group K Wolfsburg beat Feyenoord 1-0 to pip the Dutch club to second place.
The 24 sides through from the group phase join the eight third-placed finishers in the Champions League in Monday's draw, including Manchester United and Ajax Amsterdam.
Tottenham's Mourinho, who won the UEFA Cup with Porto and Europa League at Manchester United, is clearly relishing the prospect of going all the way with the Premier League leaders.
His side opened the scoring in the 57th minute when Gareth Bale's superb free kick was clawed against the post by Alireza Beiranvand but Vinicius was on hand to convert from close range.
Bale, Vinicius and Harry Winks were immediately substituted with Mourinho sending on big guns Harry Kane, Son Heung-min and Tanguy Ndombele but it was the livewire Argentine midfielder Lo Celso who sealed the victory with a neat finish.
"The game is open, when I thought about the changes the result was 0-0 then we scored a goal but that didn't change my mind," Portuguese Mourinho said of his substitutions.
Topping the group means Spurs will be seeded in the draw and avoid the big guns who have dropped out of the Champions League.
Dinamo Zagreb came within 13 minutes of becoming the first team to go through a Europa League or Champions League group stage without conceding a goal before CSKA Moscow struck a consolation in a 3-1 defeat. Zagreb topped Group K.