Jonny Wilkinson remains sidelined for Newcastle's clash with Wasps on Sunday but is expected to be available a week later.
An ankle injury has prevented England fly-half Wilkinson from playing since the 15-6 World Cup defeat by South Africa nearly five weeks ago.
His Newcastle and England team mate Toby Flood will also miss the Guinness Premiership showdown at Wasps after rolling his ankle.
Both players are expected to be fit for the EDF Energy Cup clash against the same opposition a week on Saturday.
Newcastle director of rugby John Fletcher said: 'Jonny's ankle hasn't settled as much as we thought it would. He's had an injection this week to get the inflammation down a bit. He was very close to playing this weekend and did most of our training throughout the week. He will resume full training on Monday and will be in contention for selection for the following game.
'Toby being out is a frustration as well because he'd recovered from his previous injury and then just rolled his ankle in training on Monday.'
Newcastle have named a starting line-up featuring 14 English players and 10 academy graduates for Sunday's trip to Wycombe.
Fletcher said: 'We are a regional side representing the north-east and Cumbria, and we want to give opportunities to good regional players.
'I'm a massive believer in the fact that domestic competitions have a responsibility to produce players for the national team.
'The easiest thing to do would be to go and buy a team full of South Africans or Pacific Islanders who can play 22 Premiership games a season.
'That would be a decent team, but what benefit would there be to English rugby or north-east rugby by doing that?
'First and foremost I'm a Geordie, but secondly I'm English, and we all have a duty to support the English game.
As head coach Stuart Lancaster polishes the axe he will soon wield over his World Cup training squad, Exeter Chiefs coach Rob Baxter has backed Jack Nowell, Henry Slade and Luke Cowan-Dickie to be given a stay of execution.
Italy Under-20s held off a late Samoa blitz to retain their place in the World Rugby U20 Championship on Saturday and head coach Alessandro Troncon believes the experience will have served as a valuable lesson for his young troops.