The England defender was pictured inhaling the legal but potentially lethal nitrous oxide.
Villas-Boas told reporters in a press conference today: “I spoke with him before the story came out, because the incident was a long time ago.
“The timing of the release of this news is something that surprises me. But you wouldn’t expect him to do it again.
“He has assured me of what he has said publicly and what he told me before. He told me he was in the state of mind [to play] for England so I do not see any problems.”
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