England captain Owen Farrell will miss the entire Six Nations with an ankle injury that requires surgery.
Farrell, who has not played since limping out of England’s win over Australia in November was set to make his comeback for Saracens last weekend.
However, he injured his other ankle in a training-ground collision.
Farrell is set to undergo surgery later on Wednesday with Saracens saying they expect him to be out for eight to 10 weeks.
“It’s a massive blow for him personally and for the team it’s a blow,” Jones said.
“But it’s obviously an opportunity for other guys to step up into leadership roles and for other players to play for that 12 jumper.
“We see it more as an opportunity. In today’s rugby, having your best team on the field is a rare occurrence. We’re pretty used to it. There’s an opportunity there to build a bit more leadership depth.”
England’s preparations for the tournament have been hit by a series of problems.
Centre Manu Tuilagi is rated as only having a 50% chance of playing any part in the tournament after suffering a set-back in his recovery from a hamstring problem, while wing Jonny May could also be sidelined for the duration with a knee injury.
Courtney Lawes, seen as most likely to be promoted to captaincy in Farrell’s absence, has been unable to train as he continues to work his way back from a concussion, while prop Joe Marler is isolating after contracting Covid for the second time in less than three months.
England’s first fixture is against Scotland on 5 February.
Analysis
BBC rugby union correspondent Chris Jones
It was only last week that Eddie Jones retained Farrell as captain, putting great faith in him to restore peak form and fitness after a difficult couple of seasons.
But a freak training ground injury to Farrell’s other ankle has scuppered Jones’ best-laid plans, and after a few days of conjecture and uncertainty, it’s been confirmed Farrell needs surgery and will play no part in the Championship.
It will be the first Six Nations Farrell has missed in seven years, and will force Jones to rethink both his play-making and leadership plans.
While Marcus Smith is the man in possession of the number 10 shirt, there is a lack of experience in the midfield, while Courtney Lawes’ expected appointment as stand-in skipper has been delayed by his return from concussion.
More to follow.