Wales midfielder Joe Allen says his Liverpool teammate Martin Skrtel would not give him hints on their Group B rivals Slovakia.
Allen, 26, and 31-year-old Skrtel have played together at Liverpool since the 2012-13 season, but the Slovakia international would not give details.
"I've been trying to get information from him but he has not been very forthcoming," Allen said.
"We've had a joke about it throughout the season as it's drawn closer."
Wales face Slovakia in their first game of the European Championships on 11 June and Allen says the squad have prepared for the task ahead of them.
"We'll do our homework and make sure we know exactly everything about them, what we're coming up against," he told BBC Wales Sport.
"When that first game comes around, like we've done in recent times, we'll know exactly what's necessary to come through the game with three points."
Chris Coleman's side play England in their second Group B game on 16 June and Allen believes their familiarity with much of England's squad can work in their favour.
"The one positive thing from that fixture is they have players that we know well that most of us come up against week in week out for our clubs," Allen continued.
"The fact that they're not such an unknown quantity might be something that will help us and we'll try and use that as best as we can."
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