Welcome to the Best Team Ever bracket series, where the greatest of all time have their most dominant seasons stacked up against each other until we ultimately crown a champion in each sport. The tournament will be decided by fan vote, so be sure to submit yours below! The first round of polling closes at 1 p.m. ET/10 a.m. PT on Tuesday, March 31.

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2008-09 Barcelona vs. 2015-16 PSG

No. 1: 2008-09 Barcelona

• Won Spain’s first treble.

• Earned six trophies total.

• Playing style ushered in new era.

After clearing out Ronaldinho and several other veterans, Barca handed the keys to a 21-year-old Lionel Messi in the system designed by first-year manager Pep Guardiola. Their treble — aka the top three trophies available in a season, most commonly associated with winning the Champions League, domestic league and domestic cup — was the club’s first, but their tiki-taka revolutionized the sport.

No. 16: Paris Saint-Germain

• Won Ligue 1 with record 96 points..

• Earned second of three domestic trebles.

• 50-goal scorer in Zlatan Ibrahimović.

Laurent Blanc’s collection of stars strolled to a domestic treble, winning Ligue 1 by an astounding 31 points. But PSG once again fell short in Europe, crashing out to Manchester City in the quarterfinals.

1994-95 Ajax vs. 2009-10 Inter Milan

No. 8: 1994-95 Ajax

• Won Champions League and Dutch Eredivisie.

• Scored 106 goals in league play.

• Stocked with future stars at bigger clubs.

With a team full of teenagers, Louis van Gaal’s side didn’t lose a single Eredivisie game all season, while scoring more than three goals per game. Ajax didn’t lose in the Champions League either, dispatching mighty AC Milan in the final.

No. 9: 2009-10 Inter Milan

• First and only Italian team to win a treble.

• Sneijder/Cambiasso/Zanetti midfield dominant.

• UEFA club GK of the Year in Júlio César.

Jose Mourinho coaxed a treble out of an Inter side that had just been through a major reconstruction, selling Zlatan Ibrahimović to Barca and bringing in playmaker Wesley Sneijder, among others. The results were immediate.

2019-20 Liverpool vs. 1996-97 Juventus

No. 5: 2019-20 Liverpool

• On pace to smash EPL points record.

• Went a record 27 league matches before first loss.

• Spent all but one matchweek in first place.

Jurgen Klopp’s supercharged pressing machine won the Champions League in 2019 and somehow got better, sweeping aside all comers in building out a 25-point Premier League lead, all but clinching a first title since 1990 before the coronavirus pandemic.

No. 12: 1996-97 Juventus

• Won Serie A.

• Conceded 31 goals in 45 league/European matches.

• Ballon d’Or finalist in Zinedine Zidane.

The middle season of Juve’s three consecutive Champions League finals was also the first of back-to-back Serie A titles. But this was Marcelo Lippi’s best incarnation, with a newly arrived Zinedine Zidane dazzling until their side was upset by Borussia Dortmund in the final.

2016-17 Real Madrid vs. 2017-18 Manchester City

No. 4: 2016-17 Real Madrid

• First Champions League/La Liga double in club history.

• Collected four trophies in all.

• Scored two or more goals in 52 matches.

While the middle one of its three successive Champions League titles, the 2016-17 campaign was the only one that also yielded a La Liga title and a Club World Cup. The Champions League trophy was clinched with a 4-1 thumping of Juventus.

No. 13: 2017-18 Manchester City

• Set EPL points record with 100.

• EPL record +79 goal difference.

• Also won League Cup for double.

The first Premier League team to 100 points was likely the halcyon of Pep Guardiola’s time in England, with his side so systematically dismantling opponents it looked entirely unfair. A League Cup was the cherry on top, but crashing out to Liverpool in the quarterfinals of the Champions League still stings.

1998-99 Manchester United vs. 2003-04 Porto

No. 2: 1998-99 Manchester United

• First and only treble in English history.

• Lost four games total all campaign.

• At best in pressure-filled moments.

Sir Alex Ferguson’s best team reached its apex with a treble that was never comfortable — winning the league by a point, the FA Cup after two extra-time semifinals with Arsenal, and the Champions League on two injury-time goals. But it was a treble nonetheless.

No. 15: 2003-04 Porto

• Did Champions League/Primeira Liga double.

• One of two teams outside of big five leagues to win Europe.

• Launched career of Jose Mourinho.

Jose Mourinho announced himself on the world stage with this talented young team, which won the Portuguese league but lost the cup final on penalties. They would not be denied in Europe, however, eking by Manchester United in the round of 16 before marching to the crown.

2004-05 Chelsea vs. 2007-08 Manchester United

No. 7: 2004-05 Chelsea

• EPL record 95 points stood for 13 years.

• Unbeaten over last six months of league season.

• Flashpoint side of big-spending modern era.

In one of the most impressive feats of his career, Jose Mourinho took a club that hadn’t won the league in 50 years and ran away with it on the strength of half a new squad, losing just once. The Blues lost the Champions League semis to Liverpool by a single goal, after knocking out Barcelona and Bayern Munich.

No. 10: 2007-08 Manchester United

• Won Champions League and Premier League.

• Avoided defeat in 13 Champions League matches.

• Cristiano Ronaldo scored 42 goals in all competitions

Anchored by young forwards Cristiano Ronaldo, Wayne Rooney and Carlos Tevez, this was perhaps Ferguson’s most talented team, winning the Premier League and the Championship League, but falling short of a treble in a sixth-round FA Cup upset by Portsmouth.

2014-15 Barcelona vs. 2003-04 Arsenal

No. 6: 2014-15 Barcelona

• Became only European club to win second treble.

• Scored 175 goals across all competitions.

• Knocked Man City, PSG, Bayern, Juventus out of Champions League.

The aesthetes will prefer the 2008-09 team, but Luis Enrique’s more direct outfit repeated the treble behind the trio of Lionel Messi, Neymar and the newly signed Luis Suarez, who combined for a world-record 122 goals.

No. 11: 2003-04 Arsenal

• One of two English sides in history to finish top flight unbeaten.

• Six players named to PFA Team of the Year.

• Named “Best Team” at Premier League 20 Seasons Awards.

Arsene Wenger’s Invincibles ran away with their second league title in three years without suffering a defeat — albeit with a rather sizable 12 draws. But the Gunners were knocked out in the semifinals of both domestic cup competitions and the quarterfinals of the Champions League, to upstarts Chelsea.

2012-13 Bayern Munich vs. 2000-01 Bayern Munich

No. 3: 2012-13 Bayern Munich

• First German treble winner.

• Won Bundesliga by 25 points.

• Only three losses in all competitions.

Jupp Heynckes’ swaggering German juggernaut broke 30 records on its way to a treble that produced 151 goals in 54 games, with a mere 33 goals conceded and three losses suffered.

No. 14: 2000-01 Bayern Munich

• Did Champions League/Bundesliga double.

• Won three trophies.

• Ballon d’Or finalist in Oliver Kahn.

Bayern finally got its due two years after United’s shocking comeback with its first European crown in 25 years, a win over Valencia on penalties in the final. Ottmar Hitzfeld’s disciplined side won the Bundesliga — with a mere 63 points! — and the since-abolished German League Cup as well.

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