Winning the 'treble' of league, domestic cup and European titles in a single campaign is truly special.
Very few teams in history have managed to pull off the seemingly impossible task.
In the Champions League-era in particular, there have been only six instances of a side winning the continental treble, accounted for by only four sides.
European powerhouses Barcelona and Bayern Munich are the only sides in history to have won two trebles. While Manchester United and Inter Milan are the other teams to have pulled off the feat once.
But these insane records wouldn't have been possible without the heroics of their players, who performed week in week out over 60 games to achieve incredible glory.
Only a handful of players have the distinction of winning the treble, but who are the greatest to have done it? Here's a list of the top five:
#5 Ryan Giggs
One of the greatest one-club men of all-time, Ryan Giggs was an integral part of Manchester United. He was key in the squad which romped to the first-ever treble of the Champions League era in 1999.
Only 26 at the time, the Welshman was a reckoning force in midfield. His highlight of the memorable Chapions League campaign was setting up Teddy Sheringham in extra-time of the final which sparked their famous comeback. That set United on their way to the treble.
He didn't look back thereafter, going on to become the face of the side that went on to dominate the Premier League in the 21st century. He even captained them in some of them.
Giggs retired in 2014 at the age of 40 with 963 appearances for the Red Devils and 34 trophies under his belt.
#4 Manuel Neuer
The only goalkeeper in the Champions League-era to win two continental trebles, Manuel Neuer is among the greatest ever players in his position. He has been the resolute backbone of Bayern Munich for a decade now.
He was a promising young talent at the time of his transfer from Schalke in 2011. But the German custodian has since etched his name among the legends in the club's folklore with a multitude of top-notch performances.
His collection of 26 titles with the Bavarian outfit includes 2013 and 2020 trebles. He put up phenomenal displays in goal on each occasion for which he also won numerous individual accolades from UEFA.
Neuer's inclusion in this list may seem controversial to a few but the 'sweeper-keeper' has been a modern day great. His on-field achievements are testimony to why he deserves a place here.
#3 Samuel Eto'o
Only four clubs have completed the European treble in the Champions League era. Samuel Eto'o remains the only player to have accomplished the feat in consecutive seasons and with two different teams (Barcelona and Inter Milan).
A Real Madrid flop, the Cameroonian ace truly made a name for himself at Mallorca. His promising displays landed him a dream move to Barcelona, where he achieved legendary status.
In his final season, Eto'o played a crucial role in the league, the cup and European treble. He netted 36 goals in 52 games, including one in the Champions League final against Manchester United.
He moved to Inter Milan in the summer of 2009 and repeated the trick the following May with Jose Mourinho's swashbuckling team. In the process, he created a unique record that will not be equaled in a long time.
#2 Andres Iniesta
Very few players in modern Spanish football history can claim to have had a footballing brain quite like Andres Iniesta. The midfield wizard oozed class with every touch on the ball.
During his 16 illustrious years at Barcelona, the Spaniard accomplished a lot of things. He forged an impeccable partnership with Xavi to guide the side to numerous accolades in this century.
But winning the continental treble in 2009 and 2015 remains two of his best moments. His passing genius, coupled with an eye for scoring chances played a big part in taking rival sides apart.
He has 950 career appearances and 35 titles under his belt, including the World Cup he won with La Roja in 2010, followed by consecutive Euro titles. Iniesta is certainly one of the greatest to have won the European treble.
#1 Lionel Messi
Lionel Messi is widely considered the greatest player of all-time in many quarters. So it's not surprising to see he's won the European treble. Not once, but twice.
Among the many glorious achievements of his illustrious career, it would certainly rank somewhere near the top. La Pulga was a key figure for Barcelona on both occasions.
Ahead of the 2008-09 season, he inherited the number 10 jersey from Ronaldinho and truly came of age. He took the world by storm with his goalscoring feats and insane skills.
It all came to a head in the final against Manchester United when he scored an iconic header.
Messi didn't look back thereafter, winning plenty more team and individual honors. Half a decade later, in 2015, the Argentine ace guided the Catalans to another epic treble victory, scoring 59 goals in the season.
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