Dominic Calvert-Lewin could miss up to a month for Everton witk a ‘freak’ knee injury.
Calvert-Lewin missed most of the previous campaign with myriad fitness issues before returning to help Frank Lampard’s side stave off relegation.
But the England international now faces the prospect a fresh spell on the sidelines with an injury sustained during a training session on Tuesday.
He has already been ruled out of the Blues’ Premier League opener against Chelsea amid concerns that this latest setback could lead to another absence.
Lampard faces a selection dilemma for Saturday due to Everton having no established strikers with Salomon Rondon serving the last match of a three-game ban.
He said: “We are assessing Dom’s injury.
“No timeframe has been confirmed and we are pretty sure what level it is, so we are hopeful it is not long term.
“We’ll miss him for Chelsea. He was looking in great physical condition and was training really well. It was a freak injury in training, which does happen.
“It’s a shame but we have to find the solutions to keep ourselves strong without Dominic before he returns.”