Barcelona have suffered a 1-0 defeat to Inter Milan in the Champions League on October 4 and it has sent Twitter into meltdown.Barca dominated possession early on, but Inter had better chances in the first half. The Serie A side could have had a penalty in the 23rd minute after Eric Garcia handballed in his box.However, VAR intervened, and Lautaro Martinez was adjudged to have been offside in the process.The Nerazzurri took the lead in the dying embers of first-half stoppage time. Hakan Calhanagou found space on the edge of the Barca box to fire past Marc-Andre ter Stegen.Barcelona came out with intent in the second half and had numerous opportunities at goal.Ousmane Dembele went close in the 60th minute when his shot hit the post as the Blaugrana pressurized.The Catalan giants thought they had equalized in the 66th minute when Pedri tapped in from close range following a problematic Dembele cross.Pedri's celebrations were cut short when referee Slavko Vincic headed to the VAR pitchside monitor to check if there was a handball by Ansu Fati in the build-up.His judgment was that the young Spaniard had used his hand, much to the ire of Barca boss Xavi.The Spanish tactician received a booking for his protests as he stared down the barrel of a second consecutive defeat in Europe's elite club competition.Barcelona bombarded Andre Onana's goal, but the Cameroonian goalkeeper was superb for Simone Inzaghi's side.Despite sustained pressure from Barca and a penalty appeal being waved away late on, Inter saw out a vital victory that sees them sitting second in Group C.Meanwhile, the Blaugrana are now third and trail the Serie A side by three points and have it all to do to qualify for the knockout stages.Here are some reactions from fans on Twitter to a huge setback for Xavi's men:Europa League 🌏@DhruvJh30462590Welcome back Barcelona 1Welcome back Barcelona ❤️Barça Universal@BarcaUniversalDembélé in the first half against Inter:- 0/3 dribbles completed- 1/9 crosses- 0/4 duels won- 1 shot off target- Lost possession 20 times- 2 key passes1459144Dembélé in the first half against Inter:- 0/3 dribbles completed- 1/9 crosses- 0/4 duels won- 1 shot off target- Lost possession 20 times- 2 key passes https://t.co/obhjgMXecIFC Barcelona@FCBarcelonaGOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!59201170GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!GOAL PEDRI!FC Barcelona@FCBarcelonaNOOOOOO!!!!! VAR CHECK SAYS NO GOAL! The cross was slapped away by André Onana and grazed the hand of Ansu Fati before Pedri found the net.#InterBarça | @ChampionsLeague138891NOOOOOO!!!!! VAR CHECK SAYS NO GOAL! The cross was slapped away by André Onana and grazed the hand of Ansu Fati before Pedri found the net.#InterBarça | @ChampionsLeagueAli Mahmoud@AliMahm57695310@FCBarcelona @ChampionsLeague The man behind the VAR551@FCBarcelona @ChampionsLeague The man behind the VAR https://t.co/VYGjVMTP6rEmil G@emilini9320@FCBarcelona @ChampionsLeague ROBBED!12@FCBarcelona @ChampionsLeague ROBBED!😡😡😡AMAKOM JOEY B(Parker)👑🔑🙏🏾🌎🇬🇭🇿🇦@Amakomjoeyb@BarcaTimes Dembele and Raphinha shouldn’t play together341@BarcaTimes Dembele and Raphinha shouldn’t play together✍️ 🇦🇱@10blendedWe need to find a 2nd wife for Dembele the effect from the first one has worn off, let’s gather the relatives inshallah56980We need to find a 2nd wife for Dembele the effect from the first one has worn off, let’s gather the relatives inshallahZahid🕊️⚡@AfghanforevrBarcelona returning to their rightful home, the Europa league 🏻 don’t worry though.. frankfurt are in the UCL this timeBarcelona returning to their rightful home, the Europa league 🙏🏻 don’t worry though.. frankfurt are in the UCL this timeSosa@xDMCAbreachP90We let Calhanoglu score just play the europa league anthem in camp nou already we deserve it247We let Calhanoglu score just play the europa league anthem in camp nou already we deserve itSquawka@SquawkaHakan Çalhanoğlu's goal against Barcelona was his first in the Champions League since September 2016.Worth the six-year wait. #UCL23424Hakan Çalhanoğlu's goal against Barcelona was his first in the Champions League since September 2016.Worth the six-year wait. ✨#UCL https://t.co/8FlYi3VaaFMartine🔰@martineUTDLewandowski has left one of the best teams itw just to play Europa League football with Barca473Lewandowski has left one of the best teams itw just to play Europa League football with Barca https://t.co/RJQDUPVVlX🇦🇱🇽🇰@Valv3rdeGOATLewandowski vs Inter Milan All goals & highlights 4k best player in the world?? 🥶 🥶 UCL shaking , 6th is coming home??8610Lewandowski vs Inter Milan All goals & highlights 4k 🔥🔥best player in the world?? 🥶 🥶 UCL shaking 😈😈😈😈, 6th is coming home??❗️❗️⁉️⁉️⁉️⁉️ https://t.co/nxTeohPavFDON@DonZizou_v3Barella is levels above Pedri211Barella is levels above PedriSodikov_mukhammadsodik@the_sodikof@FCBarcelona @ChampionsLeague Xavi out@FCBarcelona @ChampionsLeague Xavi out𝔸Z 𓅓@devil_may___cryXAVI IS FRAUD. WHAT A BUMXAVI IS FRAUD. WHAT A BUMFC Barcelona@FCBarcelonaFull Time #InterBarça2588273Full Time #InterBarça https://t.co/z0PA50u2BpMarwanović .@Marwan7vic@FCBarcelona @ChampionsLeague443@FCBarcelona @ChampionsLeague https://t.co/0Bbl6nmNWj.@_pstu_@FCBarcelona @ChampionsLeague How is this not a penalty????19510@FCBarcelona @ChampionsLeague How is this not a penalty???? https://t.co/0SQDyqSP08.@wurish7@FCBarcelona @ChampionsLeague Barca really think they can cheat this not the famers league it champion league 🤣🤣lets all laugh at barca 🤣🤣15@FCBarcelona @ChampionsLeague Barca really think they can cheat this not the famers league it champion league 🤣🤣😭😭lets all laugh at barca 🤣🤣21@Leon2huncho@ManagingBarca Lewandowski is the Snapchat icon in big games6@ManagingBarca Lewandowski is the Snapchat icon in big gamesEmil@BGD0026@ManagingBarca This ref is gonna ruin our season. What a joke! Why didn’t he go to the screen to see the situation for himself? It’s so unbelieveble. They don’t want us back dominating Europe.@ManagingBarca This ref is gonna ruin our season. What a joke! Why didn’t he go to the screen to see the situation for himself? It’s so unbelieveble. They don’t want us back dominating Europe.Inter@Inter_en𝐌𝐀𝐒𝐒𝐈𝐕𝐄. #InterBarça 1-0 (FT)#UCL #ForzaInter427110𝐌𝐀𝐒𝐒𝐈𝐕𝐄. #InterBarça 1-0 (FT)#UCL #ForzaInter https://t.co/mSE9jv0FNzBarcelona slip up in the Champions LeagueA difficult night for BarcaMany have touted Barca as one of the favorites to lift the Champions League come May next year.The signings of Robert Lewandowski (who was extremely quiet tonight), Jules Kounde and Raphinha have enthused Blaugrana fans.Yet they have handed Inter the initiative in the race for a likely second-place finish in Group C.Bayern Munich are flying in first, with three wins out of three.Barca will know they need to beat Bayern on October 26 with Inzaghi's men facing minnows Viktoria Plzen on matchday four who are without a single point.It is a worrying time to be a Barcelona fan as they may just be heading back to the Europa League for the second year in a row.