Cesc Fabregas tops WhoScored's list of debuts from the weekend but you might also be surprised to see Patrick van Aanholt and Andrew Robertson in there...
We could have done practically a whole quiz on Chelsea's loanees but instead we've gone for the traditional one question per club...
1) Name the Greek player who came on in the first game and earned them a draw against Poland.
2) Which Russian player took seven shots in their opening game against Czech Republic, without any of them being on target?
3) Who does Danish goal scorer Michael Krohn-Dehli play club football for?
4) Who scored Ireland's only goal of the tournament?
5) Why was England's first group game against France unusually peaceful?
6) Who was Nicklas Bendtner celebrating scoring against when he revealed those pants?
7) Why is Jesus Navas the odd one out of Spain's goal-scorers (in open play) so far in the tournament?
8) Who scored Sweden's two goals against England?
9) Which seven members of the England squad played no part in the tournament?
10) Two members of the Ireland squad play their club football outside of England - name them.
11) Which Croatia player has recently secured a move to Bayern Munich?
12) Name the substitute who saved Portugal with a late goal against Denmark.
13) Which was the top-scoring game in the tournament (not including penalty shoot-outs, smartarse) so far?
14) Where did Marco Reus, who scored for Germany against Greece, play last season?
15) For which club does Helder Postiga currently play?
16) Can you name the four players who scored their penalties for Italy against England?
17) Name the four members of England's starting XI against Italy not to have a Premier League medal.
18) True or false - Germany have never lost a game Miroslav Klose has scored in.
19) Three players in Spain's starting XI against Portugal did not come from either Real Madrid or Barcelona - name them.
20) Why might Ricardo Montolivio have had slightly split loyalties in the Italy v Germany semi-final?
Done? Have some answers.