Chelsea, Valencia and Lazio shook things up in England, Spain and Italy by climbing to the top of their respective leagues.
Chelsea replaced Arsenal as Premier League leaders after Arsene Wenger's men were stunned at home by unfancied Hull City, while Valencia moved above Villarreal in the Primera Liga on goal difference.
Lazio capitalised on Inter Milan's 1-0 defeat by city rivals AC Milan to establish a one-point advantage in Serie A. The lead also changed hands in the Bundesliga.
Arsenal were knocked off the top of the Premier League by Chelsea after suffering a shock 2-1 home defeat by Hull City.
Goals by Geovanni and Daniel Cousin stunned the Gunners after they had gone ahead through an own goal.
Chelsea moved top with a 2-0 win at Stoke City while Liverpool are keeping pace with the frontrunners thanks to a Fernando Torres brace in a 2-0 win at Everton.
Manchester United began to climb the table after a slow start, although they needed a controversial Cristiano Ronaldo penalty to set them on the way to a 2-0 defeat of Bolton Wanderers. Wayne Rooney was also on target.
Chelsea and Liverpool both have 14 points, one ahead of Aston Villa who climbed to third with a 2-1 defeat of Sunderland. Arsenal have 12 points.
Tottenham Hotspur are bottom with no victories from six games after a 2-0 defeat at Portsmouth.
Two second-half goals from David Villa and one from Joaquin put Valencia top of the Primera Liga when they came from behind to beat Deportivo Coruna 4-2.
Valencia have 13 points from five games, with Villarreal second on goal difference after they defeated newly promoted Sporting Gijon 1-0.
Champions Real Madrid are a point adrift in third place after grabbing a 2-1 away win over 10-man Real Betis with an injury time goal from Ruud van Nistelrooy.
Barcelona also snatched victory in stoppage time when Lionel Messi converted a penalty deep into injury time to seal a 2-1 win over cross-town rivals Espanyol.
Crowd trouble forced the referee to halt the derby for several minutes after a flare was thrown from the upper stands and landed near fans below.
Striker Ronaldinho headed in the only goal in AC Milan's derby against Inter Milan, handing the champions their maiden Serie A defeat under new coach Jose Mourinho.
Lazio seized the top spot by beating Torino 3-1 away with a strike by forward Goran Pandev and a double from Argentine Mauro Zarate.
Napoli are also flying high in second place after they won 1-0 at Bologna with a late German Denis goal.
Last year's runners-up AS Roma recovered from a poor spell of form to beat Atalanta 2-0, while Juventus were held to a goalless draw at Sampdoria.
Lazio lead the standings with 12 points from five games, one ahead of Napoli. Udinese are third, level on 10 points with Inter who dropped to fourth. AC Milan moved up to sixth.
Seven-times champions Olympique Lyon extended their lead to five points with a 2-1 win over Nancy after France striker Karim Benzema scored his sixth goal in seven league games.
Lyon top the table on 19 points from seven games, with surprise package Toulouse second five points back and Olympique Marseille in third, a further point adrift.
Toulouse, who have not won a significant title since 1957, moved into second by winning 1-0 at Valenciennes courtesy of a goal in added time by Andre-Pierre Gignac.
Marseille had to be content with a 1-1 draw at Le Mans on Saturday and have now gone five matches without victory in all competitions.
The former European champions claimed they should have been awarded a second goal on a header by Mamadou Samassa but the referee ruled the ball had not entirely crossed the line.
The Bundesliga's two Champions League teams had wildly contrasting fortunes on a weekend when the last two unbeaten records in the division fell.
Bayern Munich slipped to ninth place, five points behind new leaders Hamburg SV, when Juergen Klinsmann dropped his most creative players and then, predictably enough, saw the team lose 1-0 at Hanover 96 in a dour game.
Werder Bremen enjoyed a frantic 5-4 win at home to 1899 Hoffenheim, who came back from 4-1 down to draw level at 4-4 only for the 10-man home side to snatch a winner through the outstanding Mesut Ozil.
The sixth round of matches began with leaders Schalke 04 losing 1-0 at Cologne on Friday night and finished with VfL Wolfsburg, the only other unbeaten team before the weekend, going down 2-1 at Karlsruhe.
Hamburg are the new leaders with 13 points after they won 1-0 at home to Borussia Moenchengladbach. Bayer Leverkusen are second on 12 points, Werder third with 11.
Groningen registered their third win this season beating 10-man Feyenoord 3-1 to go on top of the Dutch league. They are a point ahead of PSV Eindhoven and NAC Breda.
PSV created a number of chances against bottom side Volendam but had to wait until the 73rd minute before Stijn Wuytens broke the deadlock.
NAC scored four first half goals to beat Heerenveen 4-2, while Ajax Amsterdam hit three after the interval to brush aside Vitesse Arnhem.
Steve McClaren's Twente Enschede beat Graafschap Doetinchem 3-0 to climb to fourth two points behind the leaders.