Real Madrid's failure to convert dominance into goals could have cost them dear in their 2-1 win over Olympiakos Piraeus in the Champions League.
Manchester United's big-money signing Marouane Fellaini faces several weeks on the sidelines after having an operation on his wrist.
The Journalists Newspaper reported that the Greek champions' place in Europe's elite competition would be at risk if corruption claims against club president Marinakis were proven.
Manchester United midfielder Michael Carrick is likely to be out for up to a month with an ankle injury in a further blow to the troubled Premier League champions, British media reported on Friday.
Greek Super League leaders Olympiakos Piraeus set a club record 17 successive league wins by beating Levadiakos 3-1 at the Georgios Karaiskakis stadium on Sunday.
Dinamo Zagreb midfielder Arijan Ademi failed a drug test after their Champions League match against Arsenal last month and is under investigation by UEFA, the club said on Wednesday.
Barcelona were held 1-1 at home by Napoli in the first leg of their Europa League knockout stage playoff
Former France defender Eric Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'.
Holders FC Barcelona have been placed in Group E, along with Bayer Leverkusen, AS Roma, Dinamo Zagreb.
Arsenal enjoyed an easy 2-0 victory at Aston Villa on Sunday to soar to the summit of the Premier League and leave their hapless opponents rooted at rock bottom.
Arsenal's Laurent Koscielny is the best defender in the Premier League, according to former England and Manchester United centre-back Rio Ferdinand. Ferdinand also praised the Gunners backline in Wednesday's impressive 3-0 Champions League win over Greek champions Olympiakos Piraeus, which sealed their progress to the knockout stages for a 16th consecutive year.
Panathinaikos secured a Champions League qualifying spot by beating PAOK Salonica 2-0 on Sunday to extend their lead in the Super League playoffs to a eight points with two matches left.
Pep Guardiola's ManchesterCity will play Romanian side Steaua Bucharest in the Champions League playoff round after the draw was made in Nyon on Friday.
Manchester United's dwindling hopes of lifting a trophy this season are dangling by a thread after they produced an abject display to lose 2-0 at Olympiakos Piraeus in a Champions League last-16 first leg on Tuesday.
Manchester United hope to feel the immediate benefit of a warm weather break in the Middle East before two important games in the next four days, manager David Moyes said on Friday.
Yet Milan's defensive frailty was punished when Konstantinos Fortounis scored from the penalty spot in the 81st minute to give his side the win that left them second in Group F on 10 points.
Manchester United manager David Moyes would have been sacked already if he was in charge of a Serie A club, according to former Chelsea coach Gianluca Vialli.
Inter Milan midfielder Christian Eriksen scored his first goal for the club since last month's move from Tottenham Hotspur to set up a 2-0 win at Ludogorets Razgrad in their Europa League last 32, first leg on Thursday. Getafe pulled off a surprise 2-0 home win over last year's Champions League semi-finalists Ajax Amsterdam, while Manchester United were held 1-1 at Club Brugge in wet and windy conditions. Wolverhampton Wanderers' Diogo Jota scored a second successive hat-trick in the competition to lead his side to a 4-0 victory over Espanyol and Arsenal won 1-0 at Olympiakos Piraeus with a late Alexandre Lacazette goal.
Ever since they were introduced by UEFA in 2012, fans all over Europe have been asking the same question: what does the official behind the goal do?
Greece indefinitely suspended its Superleague soccer fixtures on Monday after the owner of the club PAOK Salonika was filmed wearing a gun holster as he strode onto the pitch to protest about a disallowed goal.
Barcelona named former Athletic Bilbao coach Ernesto Valverde on Monday as the successor to Luis Enrique and he will take charge of the La Liga runners-up on a two-year contract.
A summary of Thursday's matches in the Europa League.
- 'We will have to play with a lot of intelligence' - 'We will be able to see a fantastic footballer on the pitch'
Ajax, semi-finalists last season, came from behind to beat PAOK 3-2 for a 5-4 aggregate win over the Greeks while Red Star knocked out FC Copenhagen on penalties after a bizarre shootout involving 22 spot-kicks.
Triple European champions Manchester United and their under-fire coach Louis van Gaal face a tricky task against little-known Midtjylland in the last 32 of the Europa League following Monday's draw.
Jose Mourinho, sacked by Manchester United last season after his reign there turned sour, has been charm personified since swapping punditry for the Tottenham job.
Thirteen teams have now qualified for the last 32 including Bayer Leverkusen, FC Zurich and Lazio who had already secured places in the next stage of the competition.
Arsenal enjoyed a 3-0 win in Azerbaijan against Qarabag in the Europa League on Thursday and AC Milan beat Greece's Olympiakos Piraeus 3-1 but Sevilla suffered a shock defeat by Russians Krasnodar.
Olympique de Marseille were the fall guys on a hectic opening night of Europa League group stage action as German club Eintracht Frankfurt returned from the south of France with a surprise 2-1 victory on Thursday.
News of all that's transpired on and off the football field.
Arsenal suffered a shock Europa League exit to Olympiakos Piraeus on away goals after a 2-1 extra-time home defeat, while Manchester United and Wolverhampton Wanderers cruised into the last 16 with emphatic aggregate wins on Thursday.
Olympiakos Piraeus secured a surprise 3-2 victory over last year's Champions League runners-up Atletico Madrid to make a dream start to their Group A campaign on Tuesday.
A rousing 2-1 La Liga victory at Real Madrid on Saturday may suggest otherwise, but Atletico Madrid are still rebuilding after losing several key players in the close season, coach Diego Simeone said on Monday.
"I've had a bit more luck than in recent weeks, so I'm making the most of it. For a striker, it always works in cycles and I know that. You can't start doubting yourself," Giroud told reporters after the game.
'It gives a strong answer to all the questions that were raised during the week'
Olympiakos Piraeus battled back from a two-goal deficit to earn a 2-2 home draw with last year's runners-up Tottenham Hotspur in their Champions League Group B opener.