After two weeks, 48 games, and 136(!) goals, only 16 of the 32 World Cup finalists remain in Brazil. The UFWC title is still in Brazil, too, and will stay in play right the way through to the final. That means the eventual World Cup winners will also be the Unofficial Football World Champions, and the official and unofficial titles will be unified. All 16 remaining teams have a chance to become football's undisputed champions. The current unofficial champions are Costa Rica, who took the title from Uruguay in their opening game, defeated Italy, and then drew with England. Los Ticos ended up topping group D, with Italy and England eliminated. They now face Greece in the Round of 16, on Sunday, 29 June, at the Arena Pernambuco in Recife. Greece qualified from group C courtesy of a last-gasp 2-1 win over Ivory Coast, having previously drawn with Japan and lost to Colombia. A stoppage time penalty converted by Georgios Samaras put the Greeks into the round of 16 for the first time in their history. (Costa Rica have reached the round of 16 once before, in 1990.) Greece have won 11 previous UFWC title matches, the last of which was in 2008 against Cyprus. Costa Rica and Greece have never played each other in senior competition. For the many newcomers to the UFWC who have joined us during the group stages of this World Cup, here's a very brief catch-up: The Unofficial Football World Championships is an international football competition contested in a simple boxing-style title system. Winners of title matches become title holders and Unofficial Football World Champions. A draw means the current holder retains the title. UFWC lineage goes back to the very first international match in 1872. Any 'A' international can be a UFWC title match, including friendlies - and of course World Cup games. You can find more information about the UFWC here. To answer one specific query that has come up over the past few days - extra time and penalty shoot-outs used to decide the outcome of an individual match DO count for UFWC purposes. (You can see the full UFWC rules here.) There cannot be a drawn match during the knock-out stages, and the UFWC title will be won or retained by the team that wins each title match - whether that is after 90 minutes, after extra time, or after penalties. So the UFWC title's path through the remainder of the tournament looks like this:

29 June: (Round of 16)

Costa Rica vs Greece

5 July: (Quarter Finals)

Winner vs Netherlands or Mexico

9 July: (Semi Finals)

Winner vs Argentina or Switzerland or Belgium or USA

13 July: (Final)

Winner vs Brazil or Chile or Colombia or Uruguay or
France or Nigeria or Germany or Algeria Of the sixteen remaining teams, only Algeria have never held the UFWC title. They've played in three title matches, but failed to win any of them. They'll have to reach the World Cup final to have a chance of winning the UFWC at this tournament. Argentina are the highest-ranked UFWC team left in the tournament, having won 57 title matches. The Netherlands have won 49, and Brazil have won 29. Germany have won 27, and France have won 25. All five of those teams are ranked among the top ten in the UFWC's all-time ranking table. The last team to unify the official and official titles was Spain, at the last World Cup in 2010. Spain won't be doing the same this year. Brazil 2014 will be the ninth World Cup tournament at which the official and unofficial titles have been unified. (The titles have also been unified outside of World Cup competitions.) The previous eight tournaments that provided undisputed champions were:

1958

Brazil

1966

England

1974

West Germany

1978

Argentina

1982

Italy

1986

Argentina

1998

France

2010

Spain Who will be crowned Undisputed Football World Champions on 13 July 2014? Let us know what you think by voting in our poll. You can also contact us and keep right up to date with all things UFWC via Twitter or Facebook. And don't forget that we'll have full coverage Costa Rica vs Greece, and the other UFWC knock-out matches, right here. [polldaddy poll=8151287]   You can find out everything you need to know about the UFWC in our official handbook, Unofficial Football World Champions, which contains a complete history of the unofficial competition. The 2014 edition, updated for the World Cup, is out now.