Arsenal may have qualified for the Round of 16 in Europa League but the way they did was horrific. Coming into the second leg with a comfortable three-goal lead, one would have thought this match was just a mere formality. Little did they know that this could have turned out to be one of their worst nights in European football.Graham Potter had said that his side would need a miracle to go further into the competition and the visiting fans thought the miracle could happen. The visitors had a positive start and were pressing high in a game where they had nothing to lose.There were two goals scored in a span of 69 seconds to send the home fans in a state of utter shock and dismay. At half-time, it looked as if Arsenal could be knocked out but an early error from the visitors inside the box led to a much-needed goal from Kolasinac.Despite going through to the next round, Twitterati couldn't contain their excitement. Here are some of the best reactions that we managed to find.It's defeat on the night - but our aggregate score means we're into the last 16 of the @EuropaLeague #AFCvOST pic.twitter.com/HhtLNNU2sH— Arsenal FC (@Arsenal) February 22, 2018Taking a club from playing in the 4th division to beating Arsenal, much respect to Graham Potter6 - Graham Potter is just the sixth English manager to win at the Emirates in all competitions after (Alan Curbishley, Phil Brown, Harry Redknapp, Michael Appleton and Garry Monk), but the first to do so in European competition. Future. pic.twitter.com/mUFkE5RVBG— OptaJoe (@OptaJoe) February 22, 2018📅 👏- 1996: Ostersunds FK founded.- 2012: In Swedish 4th Division.- 2018: Beat Arsenal away in Europa LeagueRemarkable story!#ARSOST pic.twitter.com/m04DRngfEI— The Sportsman (@TheSportsman) February 22, 2018Have faith Arsenal fansShout out to Arsenal. We just proved anything can happen in football and suddenly im hopeful of winning the famous Carabao cup— FG (@FunnyGooner) February 22, 2018Is it too much to ask?Arsenal would be alright if:- Welbeck could finish anything- Wilshere could stay fit- Ospina wasn't sh*t- They still had Sanchez- Ozil was arsed more than 50% of the time- Mertesacker could run- Xhaka was a footballer- Wenger wasn't an actual tyrantThat's all. Easy.— Paddy Power (@paddypower) February 22, 2018Arsenal in 2017: Nothing could be more humiliating than getting battered 10-2 by Bayern MunichArsenal in 2018: Hold my wine pic.twitter.com/dYz0fFd6CV— Mike Sanz (@mikesanz19) February 22, 2018That's another way of looking at itFirst ever English club to beat Östersunds awayFirst ever English club to knock Östersunds out of Europe First ever English club to score at home against Östersunds— JB™ (@gunnerpunner) February 22, 2018Arsenal have got to do something about this if they want to challenge for the Europa LeagueArsenal's home record in European knockout games:2012 CL L16: 3-0 v Milan2013 CL L16: 1-3 v Bayern2014 CL L16: 0-2 v Bayern2015 CL L16: 1-3 v Monaco2016 CL L16: 1-3 v Barcelona2017 CL L16: 1-5 v Bayern2018 EL L32: 1-2 v OstersundsSix losses in a row now. At home.— The Beautiful Groan (@beautifulgroan) February 22, 2018Let that sink inEmirates capacity: 59,867Östersund population: 49,806Arsenal were just beat at home by a town with a smaller population than their stadium pic.twitter.com/nESRn414Jy— betclever (@bet_clever) February 22, 2018You have your answerQ: Just how crap is Danny Welbeck? 🤔A: Sergio Ramos has scored more career goals 😂 pic.twitter.com/PimbR5HeMU— ODDSbible (@ODDSbible) February 22, 2018Arsenal joining the Europa league has been the best addition to a comedy since Frank joined It's Always Sunny in Philadelphia in season 2.— Paddy (@VieiraPaddy) February 22, 2018We could have Maldini & Beckenbauer at the back and we’d still be a load of shit.— S (@wood10_) February 22, 2018Only Arsenal can make qualification feel like a punch in the gut.— Patrick Timmons (@PatrickTimmons1) February 22, 2018LMAO: #Arsenal may have qualified but Oestersunds still managed to beat them at The Emirates 😶😂 pic.twitter.com/dJLkZEhrww— ShotOnGoal (@shotongoal247) February 22, 2018Ostersund look good in white.... I'm pretending they're Real Madrid, doesn't feel so bad.... 👍#Arsenal— Carl Bövis ⚽ (@CarlBovis_AFC) February 22, 2018True StoryWatching #Iwobi play#COYG #goonerfamily #Arsenal #Gunners pic.twitter.com/wv6QeUaol8— Niki-Goonerette (@AFC1Niki) February 22, 2018