England manager Gareth Southgate said midfielder Jordan Henderson faces a race against time to be fit for this year's European Championship as the Liverpool captain continues his recovery from a groin injury.
But the 30-year-old could be out for much longer, casting doubt over his availability for the Euros which are scheduled to begin in June.
"We know it's going to be close to the end of the season and we will just have to see how it goes," Southgate said.
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"We are conscious that with any injury of that nature, there is a guide and a time defined – but that anything can happen along the way.
"In terms of promises, we can only say that Hendo himself is very optimistic about how the operation went and the prognosis that the specialist has given him as to what is possible.
"We also know he is likely to be a bit short of match minutes in high-level games. There are a lot of things to take into consideration but, at the moment, that is a decision that is a few weeks away."
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