Inter Milans stunning comeback victory over AC Milan propelled Antonio Contes men to the Serie A summit.
With perennial champions Juventus suffering a shock loss at Verona on Saturday, the Nerazzurri appeared to have wasted their chance to go top in the Derby della Madonnina.
Veteran Zlatan Ibrahimovic teed up Ante Rebic to open the scoring and then headed home himself to put Milan in control at the interval, only for Inter to storm back in an unforgettable second half.
Captain Marcelo Brozovics stunner shortly after the break had Contes side dreaming of a comeback that Matias Vecino, Stefan De Vrij and Romelu Lukaku wrapped up in style.
And the winner is INTER!#InterMilan 4-2
L’ABBIAMO VINTO NOI QUESTO #DerbyMilano! NOI! #FORZAINTER#Oscar2020#Oscars2020#Oscarspic.twitter.com/7p2PhrovJO
Inter (@Inter) February 9, 2020
Inter finished the weekend ahead of Juventus on goal difference, with Lazio a point behind after a record-breaking result at Parma.
Felipe Caicedos first-half effort secured a 1-0 win in Emilia-Romagna as Simone Inzaghis players set a new club record of 18 successive unbeaten league matches.
Elsewhere in Serie A, Jeremie Bogas last-gasp effort secured Sassuolo a 2-1 comeback win at rock-bottom Spal, while an even later Rodrigo De Paul goal saw Udinese snatch a 1-1 draw at Brescia.
Goran Pandev gave Genoa a 1-0 victory against Cagliari and Gianluca Lapadulas brace helped Lecce to a surprise 3-2 triumph at Napoli.
FT: @CAOsasuna 1-4 @realmadrid Unai García 14′; @isco_alarcon 33′, @SergioRamos 38′, @Lucasvazquez91 84′, Jovi 90’+2’#Emirates | #RMLigapic.twitter.com/jcSfQoJl6P
Real Madrid C.F. (@realmadriden) February 9, 2020
In Spain, Real Madrid and Barcelona both secured away victories as the LaLiga title race continued to heat up.
Zinedine Zidanes men were sweating when Unai Garcia headed Osasuna ahead on Sunday afternoon, only for goals from Isco, Sergio Ramos, Lucas Vazquez and Luka Jovic to wrap up a 4-1 win that heaped the pressure on Barca.
Quique Setien endured a tough time against former club Real Betis but emerged victorious at the end of a thrilling encounter.
Sergio Canales early penalty was cancelled out by Frenkie de Jong, before Sergio Busquets levelled following a fine Nabil Fekir strike. Clement Lenglets header was enough to seal a 3-2 victory on a night when Fekir and Barcas match-winner were both sent off.
Clement Lenglet is congratulated by Barcelona team-mates at Betis (Miguel Morenatti/AP)
Embattled Espanyol secured their first home victory of the season as Raul De Tomas goal saw off Mallorca 1-0 and Alexander Isaks fine week continued as he wrapped up a 2-1 win for Real Sociedad against 10-man Athletic Bilbao.
Celta Vigo won by the same scoreline at home to Sevilla as Pione Sisto completed a late comeback triumph at Balaidos.
In the Bundesliga, leaders Bayern Munich and nearest rivals RB Leipzig fought out a goalless draw.
Hansi Flicks men were unfortunate not to go into half-time in front at the Allianz Arena, but Die Roten Bullen returned from the break strongly and gained their first ever point at the Munich giants.
It ends all square. #FCBRBLpic.twitter.com/d3dClqVvOK
FC Bayern English (@FCBayernEN) February 9, 2020
In France, Paris St Germain continued their march towards another Ligue 1 title by defeating Lyon 4-2.
Goals from Angel Di Maria and Kylian Mbappe were added to by Marcals own goal early in the second half. Martin Terrier and Moussa Dembele brought Lyon back into the contest, only for Edinson Cavani to settle any nerves.
Strasbourg roared to a 3-0 victory against Reims, while Andy Delorts goal proved enough for Montpellier as they won 1-0 at St Etienne despite Junior Sambias sending-off.