La Liga leaders Real Madrid were thumped 4-0 away by city rivals Atletico Madrid to open up the Spanish title race, while Chelsea strengthened their hold on top spot in the English Premier League after a 2-1 win at Aston Villa.
Gareth Bale, Karim Benzema and Cristiano Ronaldo will be looking to rekindle some of the magic they once served up under Carlo Ancelotti on Wednesday when they face their old coach in the latest edition of Real Madrid's rivalry with Bayern Munich.
Mueller scores brace in is 200th Bundeliga match
Alexis Sanchez had equalised for the visitors, scoring on the rebound after Manuel Neuer saved his 30th-minute penalty but the Gunners suffered when captain Laurent Koscielny limped off injured to leave the defence exposed.
Bayern Munich slumped out of the German Cup semi-finals 2-0 on penalties to Borussia Dortmund.
Pep Guardiola this week offered a rare insight into the pressure he feels to deliver Bayern Munich a Champions League trophy.
Robert Lewandowski and Arjen Robben struck twice apiece as champions Bayern Munich annihilated promoted Paderborn 6-0 on Saturday to open an 11-point lead at the top of the Bundesliga.
Second-placed VfL Wolfsburg breathed new life into the Bundesliga title race with a 4-1 win over leaders Bayern Munich, who lost their unbeaten record in a dramatic restart to the league after the winter break on Friday.
Images from the UEFA Champions League matches played on Wednesday
Substitute Mario Goetze led Bundesliga leaders Bayern Munich on a second-half four-goal rampage after midtable Mainz 05 had the temerity to take a halftime lead at the Allianz Arena in Munich.
Bayern Munich eased past Nuremberg 2-0 on Saturday with Franck Ribery and Arjen Robben on target to maintain a perfect start to the season and join a cluster of teams with nine points at the top of the table.
Leaders Bayern Munich's express start to the season finally ran out of steam on Friday with a goalless draw at Eintracht Frankfurt, following 10 wins out of their 10 previous Bundesliga games.
Here is the round-up of all the football action across Europe on the weekend
Manchester United beat AC Milan 5-4 on penalties after their International Champions Cup match in Cardiff's Millennium Stadium ended 2-2 in regulation time on Saturday.
Louis van Gaal wants to recruit a new galactico match-winner for Manchester United in a bid to fulfil his ambition of bringing another Premier League title to Old Trafford before he walks away from the club in two years.
Brazil ended their home World Cup to a cacophony of boos on Saturday as the defensive errors that crushed their bid for a sixth title resurfaced in a shoddy 3-0 loss to the Netherlands in the third-place playoff match.
Bayern Munich are desperate to avoid losing a third consecutive Champions League semi-final to Spanish opponents when they host Atletico Madrid on Tuesday but coach Pep Guardiola has his work cut out to end his time in Germany on a high.
Holders Real Madrid came from a goal down to snatch a precious 2-1 victory at wasteful Bayern Munich on Wednesday and carry a considerable advantage into their Champions League semi-final second leg in Spain.
Bayern Munich are confident they have overcome a mini-slump just in time for their Champions League round of 16 second leg against Juventus on Wednesday as they chase a treble of titles this season.
"First we have to play football and see what happens. Maybe we can then score a goal and create an atmosphere in the stadium."
Bayern Munich were left to rue a number of missed chances in their Champions League last 16 first leg against Juventus on Tuesday after the Germans squandered a two-goal lead to draw 2-2 despite dominating for much of the game.
Injury-plagued Bayern Munich chasing a treble.
Bayern Munich may be missing some of their biggest names when they travel to Porto for the first leg of their Champions League last eight on Wednesday but the Germans are confident they have enough firepower to defend their favourites tag.
Bayern left fuming over Champions League 'robbery'.
The Czech Republic snatched a last-gasp 2-1 win over the Netherlands thanks to Vaclav Pilar's added time goal after a dreadful mistake by Daryl Janmaat in their opening Euro 2016 qualifier on Tuesday.
Bayern Munich have all but secured their third consecutive Bundesliga title and victory over Hertha Berlin could see them clinch it as early as this weekend.
Thomas Mueller scored twice as Bundesliga leaders Bayern Munich came from a goal down to beat Hanover 3-1 on Saturday and stretch their advantage at the top to 11 points after VfL Wolfsburg slumped to a 1-0 loss at Augsburg.
An in-form Bayern Munich will be looking to notch up their fourth straight win in the Champions League group stage and seal a spot in the final 16 when the Bundesliga champions face Viktoria Plzen on Tuesday.
The two losses in Blind's first two games left the Dutch floundering in fourth place in Group A, needing to overhaul a two-point deficit on third placed Turkey with two games to play in October to have any chance of reaching the Euro 2016 finals via the November play-offs.
Bayern, who won the Champions League in 2013, have yet to hit top form this season, with many players tired after the World Cup and others, including Thiago Alcantara, Bastian Schweinsteiger and Rafinha, out injured.
Cristiano Ronaldo scored a hat-trick to send Real Madrid through to the Champions League semi-finals with a 4-2 extra-time win and 6-3 aggregate success against 10-man Bayern Munich in controversial circumstances on Tuesday.
Barcelona's Lionel Messi is the best player ever, Bayern coach Pep Guardiola said.
Two late moments of Lionel Messi magic and a goal from Neymar helped Barcelona break the resistance of Bayern Munich in a pulsating 3-0 victory in their Champions League semi-final first leg at the Nou Camp on Wednesday.
Bayern Munich coach Pep Guardiola weathered his first major crisis at the German club, coming out stronger after his team crushed Porto 7-4 on aggregate on Tuesday to move into the Champions League last four.
Injury-ravaged Bayern Munich beat Hoffenheim 2-0 on Saturday, shrugging off a string of absences and their midweek Champions League defeat at Porto to close in on the Bundesliga title.
In-form Borussia Moenchengladbach struck three times in 14 minutes in the second half to floor champions Bayern Munich 3-1 on Saturday and inflict their first Bundesliga defeat of the season.
Holders Bayern Munich recovered from the shock of a stunning Patrice Evra goal to score three times in quick succession to beat Manchester United 3-1 and reach the Champions League semi-finals on Wednesday.
Bundesliga champions Bayern Munich suffered their first league defeat in 18 months when they slumped to a 1-0 loss at Augsburg on Saturday as Sascha Moelder's first-half strike ended their record 53-game unbeaten league run.
AS Roma's Daniele De Rossi celebrated his 500th appearance for the club with a goal in their 3-1 win over Empoli at the Olympic Stadium as they moved up to second place in Serie A on Saturday.
Napoli rediscovered their scoring touch as they brushed aside Inter Milan 3-0 on Friday, sending their opponents' new coach Stefano Pioli back to the drawing-board.