But the Premier League club have also given a more encouraging update on the hamstring injury the Cumbrian star suffered against Liverpool.
Branthwaite had to be stretchered off late in Everton's 2-1 defeat to their Merseyside rivals in Sunday's derby.
It was a latest blow for the defender from Wigton, who missed the first half of the campaign after undergoing hamstring surgery.
Everton, though, have stressed that the 23-year-old former Carlisle United player does not need to go under the knife again, after assessment of his latest injury.
In a statement, the Toffees said: "Everton can confirm Jarrad Branthwaite sustained a hamstring injury during Sunday’s Merseyside derby.
An update on Jarrad Branthwaite. 🔵 pic.twitter.com/gsjig1a3vq
— Everton (@Everton) April 22, 2026
"The injury is unrelated to the hamstring area which required surgery in October, with a scan confirming no procedure is needed this time around.
"Branthwaite will now undergo rehabilitation at Finch Farm with Everton’s medical team and is unlikely to feature again this season."
Everton's statement does not rule out the possibility that Branthwaite could return to fitness in time to make a late push for England's World Cup squad.
But it still leaves the Cumbrian facing a race against time to be available for consideration by national team boss Thomas Tuchel, who will name his squad for the 2026 tournament on June 1.
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