What a season it has been for soccer fans in Europe.

Most national leagues are complete such as La Liga, Italian Series A and the English Premier League. But, a continental champion still has to be crowned. Barcelona and Juventus will play each other in the 2015 UEFA Champions League Final on Saturday, June 6, in Berlin, Germany.

This isn't your ordinary annual Champions League Final. The winner of this game will achieve all-time great status by winning the treble.

What the heck is a treble?

The treble is a soccer term used for teams that win three championships in one season. Those three championships usually include one domestic league title, a domestic league championship and a continental championship.

Well, wouldn't you know it, both Barcelona and Juventus have won two of the three this season, and have a chance at the treble on Saturday.

Barcelona won La Liga with a 30-4-4 record giving them 94 points, two points ahead of their rival Real Madrid. Lionel Messi led La Liga with 18 assists, and had a team-high 43 goals during the season. Barcelona had just one loss in their last 21 league games. The South American trio of Mess, Neymar and Luis Suarez has been virtually unbeatable this season.

Barcelona's second championship came at the Copa del Rey. Barcelona defeated Athletic Bilbao in the finals, 3-1. Messi scored an incredible goal dribbling by defenders on the right side of the field, and Neymar added a goal as well. Barcelona has now won 27 Copa del Rey championships, the most in Spanish League soccer history.

Barcelona eliminated Bayern Munich in the semifinals of the Champions League. So far, Barcelona has won La Liga, the Copa del Rey, and will have a chance at winning the Champions League. Barcelona is the only Spanish Premier League team to achieve the treble in soccer history having done so in the 2008-09 season. A second treble for Messi would easily secure his all-time great status.

The first squad to ever win the treble was Santos of Brazil in 1962.

But, this accomplishment won't be easy for Barcelona. Standing in their way is the Italian club, Juventus. Just like Barcelona, Juventus won their league. Juventus dominated the Italian Serie A with a league-leading 87 points. Second place Roma had just 70 points and seven less victories than Juventus this season.

Juventus continued their dominating run by winning the Coppa Italia, which is Barcelona's equivalent to the Copa del Rey. Just like Barcelona, Juventus has also won the most of their domestic championships, having now won 10 Coppa Italias. Carlos Tevez (from Argentina like Messi) led Juventus in league goals scored this year with 20 and had seven assists.

Juventus has won two Champions League titles, 1985 and 1996. On the other hand, Barcelona has won four Champions League titles, 1992, 2006, 2009 and 2011. This will be the first time that Barcelona and Juventus will face each other in the finals of the Champions League tournament.

Juventus and Barcelona will face off in arguably the biggest European soccer games of all-time this upcoming weekend. The winner will automatically win the exclusive treble and make soccer history forever imprinting their names as one of the best squads ever.

What a game it should be.

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