Croatia faces racism charge as tensions continue

Croatia became the first country to be charged over racism at Euro 2012 and police and calculators were out in force before the final round of Group A matches got under way.

With Russia facing Greece in Warsaw and co-hosts Poland meeting the Czech Republic in Wroclaw to decide who qualifies for the quarter-finals, police pledged to protect thousands of fans expected in the Polish capital and avoid a repeat of Tuesday's violence.

Twenty thousand Russians and 4,000 Greeks have tickets to their match and Warsaw's 100,000-capacity fanzone is expected to be full.

Those numbers are a headache for police after Tuesday's problems when Polish hooligans set upon a group of Russian fans marching to the stadium for the politically-charged match between their respective teams.

"Smiling fans are welcome in Warsaw. But if we see others around like last time then we will detain them immediately," said Warsaw police spokesman Polish fan Maciej Kowalski.

Russia lead the group with four points with the Czechs on three, Poland on two and Greece on one.

If teams are level on points, their respective positions will be decided on their head-to-head record rather than old- fashioned goal difference, a system which is increasingly unpopular because of its complexity.