Unbeaten streaks are incredibly tricky to maintain in top European leagues. Streakholders not only need to hold their own against top-tier teams with plenty of firepower, but they also have to overcome teams playing with a low block. Additionally, injuries tend to come thick and fast thanks to fixture congestion, causing teams to lose momentum and ultimately concede their unbeaten streaks.

Over the last couple of decades, only a handful of teams have managed to secure noteworthy unbeaten streaks, and today, we will quickly examine the top 10 runs. Continue reading to check out the 10 longest unbeaten streaks across the top 10 European leagues and associated competitions since 2000:

#10 Bayer Leverkusen – 33 Games*

Bayer Leverkusen Manager & Former Player Xabi Alonso

Bundesliga leaders Bayer Leverkusen have been in dreamland under Xabi Alonso this season. The hustling-and-bustling Leverkusen have dazzled with their eye-catching gameplay, ruthless finishing, and tidy defending in all competitions, going 33 games without dropping three points.

Alonso’s side currently have an eight-point lead over Bayern Munich in the Bundesliga rankings, are in the UEFA Europa League Round of 16, and will compete in the DFB-Pokal semi-finals. They could become the first team in the top 10 European leagues to go over 50 games unbeaten, as they will play 18 more games if they reach the final of the DFB-Pokal and the Europa League.

#9 FC Porto – 36 Games

Andre Villas-Boas Won The League Title As Well As The Europa League With FC Porto

Between March and December 2010, Portuguese powerhouse FC Porto enjoyed a 36-game unbeaten run in all competitions. Jesualdo Ferreira started the streak in the 2009-10 season but it was Andre Villas-Boas who established Porto as the best in the country.

After finishing third in Primeira Liga in 2009-10, Porto claimed the title under Villas-Boas in 2010-11. They also won Taca de Portugal, UEFA Europa League, and Supertaca Candido de Oliveira that season.

#8 Paris Saint-Germain – 36 Games

Laurent Blanc Won 3 Ligue 1 Titles With PSG

Ligue 1’s sole representative on this list, Paris Saint-Germain (PSG) enjoyed a magnificent 36-game unbeaten run between March 2013 and December 2013. Under Carlo Ancelotti, Les Parisiens won the league title in the 2012-13 season. The Italian’s successor Laurent Blanc picked up right where he left off in 2013-14 and added another title.

Surprisingly, PSG’s unbeaten run came to an end against minnows Evian on December 4, 2013. They suffered a 2-0 defeat away from home.

#7 PSV Eindhoven – 39 Games

PSV Manager Fred Rutten

Dutch outfit PSV Eindhoven had a remarkable run between March 2009 and January 2010, going as many as 39 games without tasting even a single defeat. Dutch tactician Fred Rutten was at the helm during PSV’s historic run.

Unfortunately, the remarkable resilience did not result in silverware for PSV. They finished third in Eredivisie in both the 2009-10 and 2010-11 seasons and could not go beyond the quarter-final stage in the UEFA Europa League.

#6 Barcelona – 39 Games

Barcelona Manager Luis Enrique Took The Team To The Treble In 2014-15

La Liga juggernauts Barcelona strung together a 39-game unbeaten run between October 2015 and April 2016 under manager Luis Enrique. The Blaugrana’s streak-ending defeat came to Zinedine Zidane’s Real Madrid in La Liga on April 2, 2016, with Los Blancos securing a 2-1 win over their bitterest rivals at Camp Nou.

The defeat took a toll on Barca’s confidence but it did not keep them from winning the La Liga title. They also won the Copa del Rey, UEFA Super Cup, and the FIFA Club World Cup in the 2015-16 season.

#5 Inter Milan – 39 Games

Roberto Mancini Won The Serie A With Inter Milan In 2006-07

Serie A powerhouse Inter Milan went on a 39-game unbeaten run under Roberto Mancini between October 2006 and April 2007. The stellar unbeaten run created the foundation for their Serie A win at the end of the season, with him losing just one game en route to the title. That defeat, a 3-1 loss, came against AS Roma on April 18, 2007.

Inter Milan also reached the Coppa Italia semi-finals and the quarter-finals of the UEFA Europa League that season.

#4 Real Madrid – 40 Games

Zinedine Zidane Won 3 UEFA Champions Leagues With Real Madrid

The most successful club in all of Europe, La Liga powerhouse Real Madrid made history under Zinedine Zidane. Between April 2016 and January 2017, Los Blancos went 40 games without dropping all three points, winning the 2015-16 UEFA Champions League and FIFA Club World Cup along the way.

Of course, the 2015-16 Champions League victory was only the beginning, as the club went on to win it twice more in the 2016-17 and 2017-18 seasons. Madrid also added a La Liga title to their haul in 2016-17.

#3 Inter Milan – 40 Games

Roberto Mancini Managed Inter Milan In 2004-05 Season

The only team on this list to appear twice, Inter Milan were near-spotless during May 2004 and February 2005, going 40 games without losing. No team belonging to the top 10 European leagues had gone as long without defeat since the turn of the century.

With debutant Roberto Mancini managing the team in the 2004-05 season, the Nerazzuri finished third in Serie A, reached the quarter-finals of the UEFA Champions League, and won the Coppa Italia. All in all, it was an improvement over Inter’s performance under former manager Alberto Zaccheroni.

#2 Celtic – 42 Games

Celtic Coach Brendan Rodgers Oversaw 42-Game Unbeaten Run

Under the tutelage of Brendan Rodgers, Celtic enjoyed a whopping 42-game unbeaten run in all competitions between November 2016 and August 2017.

The 2016-17 campaign was a historic one for the Scottish powerhouse, as they clinched the domestic title without tasting defeat. They also won the League Cup and the Scottish Cup in 2016-17, completing the domestic Treble.

#1 Juventus – 43 Games

Juventus Won The Serie A Title After A Nine-Year Hiatus In The 2011-12 Season

Going a whopping 43 games without defeat between May 2011 and May 2012, Juventus have clinched the top spot on the rankings. The Bianconeri finished seventh in Serie A rankings in the 2010-11 season, but they went unbeaten in Serie A in the 2011-12 season, winning their first Italian top-flight title in nine years.

Juventus, who were under Antonio Conte at the time, conceded their unbeaten to Napoli in the Coppa Italia final.