VATICAN CITY — Celebrating its 10th anniversary, the Clericus Cup soccer series for priests and seminarians studying in Rome welcomed three new teams to its 2016 league.

Priests and altar boys who serve in St. Peter's Basilica are joining forces to vie for the championship title against 15 other teams, fielding players from 65 different countries in the world. Two other new teams formed this year are made up of Consolata Missionaries and the Missionary Servants of the Poor. The Missionary Servants team is actually a hodge-podge of players from eight different religious congregations that did not have enough players to field their own team, said a team spokesman.

Four of the 16 teams in the 2016 series have played since the tournament's founding. It was established in 2006 after Italian Cardinal Tarcisio Bertone — an avid soccer fan — pitched the idea to the Catholic Italian Sports Center.

During the summer madness of the 2006 World Cup, the cardinal told representatives of the center that Rome's pontifical universities were a unique, untapped treasure trove of sport-lovers from all over the world. The Pontifical Council for the Laity and later the Pontifical Council for Culture have helped sponsor the series.

Part of the series' mission is to challenge players to live out their Christian values on the field and offer the world a more ethical role model in sportsmanship. In addition to the traditional yellow and red cards signaling foul play and expulsion from the game, the tournament includes a unique "sin bin" blue card, which is a five-minute "purgatory" for players who get carried away and need time to cool down.

The Rome-based series has also been a great way for students to build team spirit with their fellow housemates and create new friendships with students from other parts of the world, said Martin Amaro, a first-year theology student from the Diocese of Little Rock studying at the North American College.

Practice and matches are a great way "to get to know the other guys," he said at the news conference Feb. 19. The North American College Martyrs won the championship trophy — a cleat-wearing soccer ball sporting a wide-brimmed clerical hat known as a "saturno" — in 2012 and 2013.

Of the more than 350 players signed up this year, the majority are from Mexico, Nigeria and the United States. Dozens of men are the sole representative of countries like Syria, China, East Timor, South Sudan and Madagascar.

Division play began Feb. 20 with top teams heading into semifinals May 21 and the final match May 28.