Kyle Walker limped out of England's friendly againstBrazil with a hamstring problem in a major injury concern for Manchester City.
The England defender came off after just 19 minutes at Wembley, after stopping an effort off the line from Vinicius Jr.
"He's not sure if it's just tightness," said Gareth Southgate after the match. "We'll know more in the next 36 hours."
The injury comes eight days before Man City host Arsenal in a crucial title race six-pointer in the Premier League, on March 31, kick-off 4.30pm.
Walker has been a virtual ever-present figure in the City defence, with 38 appearances in all competitions this season.
