After recently completing a thrilling season of club football, many players across Europe have now turned their thoughts to UEFA EURO 2012, the continental tournament which takes place in Poland and Ukraine and begins on 8 June.

Ten months of teamwork and camaraderie alongside their team-mates will count for nothing when the 14th edition of the European Championship kicks off, however, particularly for those who will find themselves on opposite sides for their countries.

The draw for the group stage, which took place in December 2011, set up several heavyweight clashes for the first round of fixtures, with Netherlands-Germany, Spain-Italy and France-England chief among them.

Star players from Europe’s biggest clubs will therefore be pitched against one another from the outset of the competition and friendship will have to be forgotten for the sake of national pride. takes a look at those who must end their allegiances for one month.

Robben against the rest
Germany against the Netherlands is a match which needs little extra edge, as the two have been fierce rivals since the 1974 FIFA World Cup™, when they contested the Final. Johan Cruyff and Co took a first-minute lead but still lost the showpiece and a mutual antipathy has festered ever since.

Their next meeting, in Kharkiv on 13 June during the second round of Group B fixtures, will see Bayern Munich players feature heavily. The beaten UEFA Champions League finalists could have as many as nine representatives on the field, but one will be massively outnumbered.

Netherlands winger Arjen Robben, who crucially missed an extra-time penalty during Bayern’s shoot-out defeat by Chelsea, may be confused by the sight of his domestic team-mates all playing for the opposition, with Holger Badstuber, Jerome Boateng, Mario Gomez, Toni Kroos, Philipp Lahm, Thomas Muller, Manuel Neuer and Bastian Schweinsteiger  in Germany’s squad.

Robben will no doubt enjoy the challenge of scoring against his defensive colleagues, which is a sentiment likely to be shared elsewhere in the group by fellow forwards Dirk Kuyt and Robin van Persie.

Kuyt will come up against Liverpool centre-back Daniel Agger in the Denmark defence when the Dutch begin their campaign on 9 June, while Van Persie could find his efforts to continue a remarkable goalscoring season blocked by Arsenal stopper Per Mertesacker.

The other Group B game on 9 June sees the Germans, runners-up to Spain at EURO 2008, take on Portugal in a match which will have a distinct Real Madrid influence. Cristiano Ronaldo and Mesut Ozil will try to dictate the tempo at either end, while Sami Khedira could find himself battling with Fabio Coentrao and Pepe.

Arsenal ties in Group A
Group A also has interesting connotations for Premier League side Arsenal, with Lukasz Fabianski and Wojciech Szczesny competing for the Poland No1 jersey. Whoever gets the nod in goal for the co-hosts will be tasked with keeping out Czech Republic captain and Gunners midfielder Tomas Rosicky.

Defending champions Spain against 2006 FIFA World Cup winners Italy is an obvious highlight of the opening round. The 10 June fixture will showcase a plethora of the continent’s best players and Manchester City duo David Silva and Mario Balotelli are sure to be among those deciding which team takes an early advantage in Group C.

Having only finalised moves to Everton in January of this year, midfielder Darron Gibson and striker Nikica Jelavic have not had much time to form a relationship, which might be for the best as they will face each other during Republic of Ireland’s first Group C encounter against Croatia.

Familiar faces for France
Perhaps the group fixture which holds the most intrigue in this regard is the opening Group D match between France and England. As many as six City players, fresh from being crowned Premier League champions, could be on opposing sides come kick-off on 11 June. Gael Clichy and Samir Nasri of Les Bleus will certainly recognise Gareth Barry, Joe Hart, Joleon Lescott and James Milner, should they be selected by Roy Hodgson.

It will be a similar story for Chelsea stars when the Three Lions take on Laurent Blanc’s men in Donetsk. If Florent Malouda features for France he could come up against Blues team-mates Gary Cahill, Ashley Cole, Frank Lampard and John Terry just three weeks after they all hoisted the Champions League trophy aloft.

As AC Milan ended the season without a major trophy, two of their players travel to Poland and Ukraine hoping to make amends with their national team. Zlatan Ibrahimovic and Philippe Mexes will face each other along the way, with the striker trying to get past the defender when Sweden meet France on 19 June.