Against Bayern Munich, the Daily Star says the 28-year-old felt significant pain in his left foot both during and after the game.
He limped home with the rest of the squad yesterday and is expected to be sidelined for several weeks.
United have just five games of the season left and are desperate to produce a strong finish to salvage some pride.
A United source said: "The chipped bone will repair itself, but it won't happen overnight.
"He had injections in Munich because it was such a huge game and his team needed him, but in truth he shouldn't have played.
"The season is coming to an end and United have little at stake, so his main priority now is to make sure he is firing on all cylinders once the World Cup preparations start."
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