Belarussian side BATE Borisov caused one of the biggest shocks ever seen in the Champions League when they stunned last season's beaten finalists Bayern Munich 3-1 on Tuesday.
Dimitar Berbatov scored twice as Manchester United beat AaB Aalborg 3-0, while Arsenal crushed Porto 4-0 with a double strike from Robin Van Persie in Champions League matches.
Arsenal had scored 10 goals in two matches against BATE Borisov in the same competition in 2017 but never looked like being as prolific in the freezing temperatures of Belarus.
Shakhtar Donetsk led the way for the Champions League underdogs as they beat holders Chelsea 2-1 while former European champions Barcelona and Manchester United came from behind to maintain perfect starts on Tuesday.
Malaga gave themselves an excellent chance of qualifying for the Champions League for the first time by beating Panathinaikos 2-0 at home in the first leg of their playoff on Wednesday.
Bayern Munich made it seven wins out of seven in the Bundesliga on Saturday as two goals from Franck Ribery led them to a 2-0 win over a toothless Hoffenheim in an embarrassingly one-sided match.
Making the most of a rare start for Sarri's side, Loftus-Cheek inspired Chelsea to a 3-1 Europa League win over the Belarus champions at Stamford Bridge on Thursday.
Barcelona coach Pep Guardiola has played down this weekend's 'clasico' match at Real Madrid by saying a European Union summit meeting on Friday and moves to save the Euro were much more significant.
Barcelona, AC Milan and Arsenal can all book places in the knockout stages of the Champions League with wins on Tuesday.
Barcelona and AC Milan can effectively seal their expected places in the Champions League knockout stage with three games remaining when they play rank outsiders Viktoria Plzen and BATE Borisov respectively in their Group H matches on Wednesday.
Lionel Messi has dismissed talk of chasing records after the Argentine struck twice in Wednesday's 5-0 Champions League win at BATE Borisov to equal Ladislau Kubala as Barcelona's second highest scorer of all time on 194 goals.
Greek soccer, already plagued by match-fixing and crowd violence, suffered more misery on Tuesday when Panathinaikos lost 4-3 at home to Odense and were knocked out of the Champions League qualifiers.
Images from the Champions League matches played across Europe on Tuesday.
Manchester rivals City and United have so far not taken their domestic form into Europe and will be among 15 teams attempting to win their first matches in the Champions League group stage this week.
Images from the Champions League matches played across Europe on Wednesday.
Holders Barcelona barely broke a sweat in a ruthless 5-0 hammering of BATE Borisov while former champions AC Milan made harder work of finding the net before overcoming new boys Viktoria Plzen 2-0 in the Champions League on Wednesday.
Another Lionel Messi hat-trick lit up the Champions League yet again as Barcelona and AC Milan qualified for the last 16 with time to spare on Tuesday although it is APOEL Nicosia who are fast becoming the talk of the group stages.
A thrilling draw away to Salzburg enabled Serbian champions Red Star Belgrade to reach the Champions League group stage for the first time where they will be joined by Portugal's Benfica and Dutch side PSV Eindhoven. Red Star, who won the European Cup in 1991, came back from two goals down in an electrifying second leg in Austria to draw 2-2 and go through on away goals.
Newcomers BATE Borisov got away lightly with a 2-0 defeat against Real Madrid at the Bernabeu in their Champions League debut in Group H on Wednesday. Sergio Ramos gave the nine-times European champions an early lead and they threatened an avalanche of goals but BATE held firm until early in the second half. Ruud van Nistelrooy doubled the advantage with his 54th goal in the competition.
Barcelona forward Lionel Messi was back in training on Monday five days before the La Liga leaders play at second-placed Real Madrid in the first of the season's two Clasicos.
Chelsea will face Dynamo Kiev at home in the first leg of their Europa League last-16 tie, while London rivals Arsenal will travel to Rennes following Friday's draw in Nyon, Switzerland.
Arsenal led a list of nine clubs who grabbed a second win in as many games in the Europa League group phase as France striker Olivier Giroud scored his 100th goal for the club in a 4-2 win at BATE Borisov on Thursday.
Rattled by embarrassing domestic defeats, Chelsea looked jittery before Olivier Giroud settled their nerves with a close range tap-in shortly after halftime at StamfordBridge following good work by N'Golo Kante and Willian in the build-up.
Red Star Belgrade, who won Europe's premier club competition in 1991, engineered a 2-0 home victory against HJK Helsinki thanks to a Richmond Boakye header and substitute Milan Pavkov's sweeping 90th-minute finish.
Visitors Ajax had looked comfortable after former Southampton winger Tadic set up the first goal with a swerving cross before drilling home the second himself.
Red Star, who won the European Cup in 1991 and reached the latter stages the following season, finished second in Group H behind Arsenal who crushed BATE Borisov 6-0.
With professional soccer at a virtual standstill around the globe, fans in need of their weekly fix are turning to the Belarusian Premier League to fill the void as it carries on with matches despite the coronavirus outbreak.
Barcelona have vowed to use all legal means to fight a second fine imposed by UEFA after fans displayed pro-Catalan independence flags during September's Champions League Group E match at home to Bayer Leverkusen.
Manchester United were given a troublesome tie against Club Bruges in the draw for the Champions League playoff round on Friday, although it could have been worse as they avoided Lazio, CSKA Moscow or Monaco.
Ajax were joined by Young Boys, who stunned Dinamo Zagreb 2-1 away for a 3-2 aggregate win over the Croatians, and AEK Athens who scraped a 1-1 home draw with FC Vidi after a 2-1 win in the first leg in Hungary.
Former European champions Red Star Belgrade, Ajax Amsterdam and Celtic all made it comfortably through to the third qualifying round of the Champions League on Wednesday after surviving away legs.
European champions Real Madrid will face former champions Liverpool, FC Basel and debutants Ludogorets of Bulgaria following the draw for the group stage of the Champions league on Thursday.
'The system is the same and we all have to contribute a bit more but it is impossible not to feel Messi's absence' 'But Neymar is also a leader for his playing style and what he brings to the team'
Lionel Messi is set for his first start for nearly two months when Barcelona, fresh from pulverising Real Madrid 4-0 at the weekend, set their sights on Champions League qualification when AS Roma visit the Nou Camp on Tuesday.
Barcelona strike duo Neymar and Luis Suarez have developed in the absence of Lionel Messi.
The goal machines of Bayern Munich, Chelsea and Shakhtar Donetsk cranked into top gear on Tuesday as the Champions League captivated its continental audience with a record 40 goals in one eight-game night.
Lionel Messi's injury is a painful blow for Barcelona but is also a motivation for the rest of the squad, midfielder Ivan Rakitic said before the holders host Bayer Leverkusen in Champions League Group E on Tuesday.
Troubled AC Milan were held to a goalless draw by AEK Athens
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