England striker Dominic Calvert-Lewin is out of Everton’s Premier League opener against Chelsea after suffering a “freak” injury in training.

Toffees’ boss Frank Lampard has confirmed the 25-year-old will miss Saturday’s clash with the Blues at Goodison Park with a knee problem.

Lampard told the club’s official website: “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.”

Calvert-Lewin, who missed four months of last season with a persistent muscle injury, is being assessed by Everton’s medical staff and undergoing treatment.