Trent Alexander-Arnold was forced off with a mystery leg injury in England's friendly win over Austria.
The Liverpool defender pulled up with a leg injury under no challenge late on into the Euro 2020 warm-up clash and needed the assistance of the England coaches as he walked around the perimeter of the pitch.
Alexander-Arnold appeared to be holding his hamstring, but he also had his hand on his knee.
Aston Villa midfielder Jack Grealish was the first England star to talk out about his teammate following the win and admitted to ITV he's worried about the Liverpool right-back.
"It didn't look good the way he was walking around the pitch," said Grealish.
"Fingers crossed he will be OK in the next few days."
England manager Gareth Southgate added: "We're going to have a little look. It’s obviously not good to see him having to come off in the way he did, but we'll have to assess him over the next 24 hours.
"I think it's the thigh, but the medical team is still assessing it.
"We'll just have to see, it’s not a good sign to see him walk off in the way that he did, so we'll know more in the next 24 or 48 hours."
England ran out 1-0 winners of Austria on Wednesday night, with Bukayo Saka scoring the only goal of the friendly from close-range in the second half at the Riverside.
The Arsenal youngster was a surprise call up to Southgate's England side, as Manchester United's Jesse Lingard missed out.
And he repaid his manager's faith with his first goal in an England shirt.
