Everton striker Dominic Calvert-Lewin has suffered a setback in his recovery from a quadriceps injury and will remain out for several more weeks.
The 24-year-old England international was side-lined by the quadriceps issue - along with a broken toe - during the opening month of the season and has not featured since scoring in a victory over Brighton on August 28.
Calvert-Lewin's setback is the latest in a series of injury blows for Everton boss Rafael Benitez, with fellow forward Richarlison yet to return from a five-game absence and midfielder Abdoulaye Doucoure having suffered a broken foot in Sunday's defeat to West Ham.
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A club statement said: "Dominic Calvert-Lewin has suffered a setback in his rehabilitation from a quadriceps injury and will remain out for a number of weeks.
"Calvert-Lewin will continue to receive specialist treatment and an update on the England international's fitness will be provided in due course."
Calvert-Lewin, who scored in each of Everton's opening three games of the season before being ruled out, was the club's top scorer last season with 21 goals in all competitions.
Benitez estimated on September 13 the forward would miss two-to-three weeks with the quadriceps injury and broken toe, but his absence has now stretched across five league matches, and the club's Carabao Cup exit at the hands of Championship side QPR.
Everton have won one of their last four Premier League games, but thanks to a strong start to the campaign remain in eighth, just five points behind leaders Chelsea.
The Toffees take on Watford, Wolves and Tottenham before the next international break in mid November, with Calvert-Lewin appearing likely to miss out on England's final two World Cup qualifiers against Albania and San Marino.