Leicester Tigers' scrum-half Ben Youngs has been ruled out of Saturday's QBE International against Argentina with a hip injury.
He had been named for the Twickenham encounter but has failed to recover sufficiently. He will be replaced by
"Ben is still suffering some discomfort in his hip area and is unable to run at full pace," England head coach Stuart Lancaster said.
"He is making good progress and should be fit for consideration next week. We are fortunate that we can call on Danny who has been playing well for Harlequins and training hard with us."
The Director of Rugby at Leicester Tigers, Richard Cockerill has welcomed the two brothers Ben and Tom Youngs to the club.
Both have signed long-term contracts and are the kind of players they want to build the club around for the future.
Leicester Tigers have announced new long-term contracts for England Internationals Ben and Tom Youngs.
The brothers both play for England and were part of last Saturday's 20-14 home defeat against Australia.
Ben made his Leicester debut five years ago and has played in four Premiership finals, winning 26 caps.
Hooker Tom, meanwhile, made his Test debut against Fiji earlier this month, having first featured for Leicester as a centre in 2006 before being converted into a front-row forward.
Both players are Leicester academy products.
Leicester scrum-half Ben Youngs has been suspended for a week by a Rugby Football Union (RFU) disciplinary hearing, after pleading guilty to striking London Irish forward Jamie Gibson with his knee.
The incident during the Aviva Premiership game on March 25 resulted in Youngs being cited - he also received a one-week suspension from the club, missing Friday's win over Worcester.
His RFU ban will run alongside his Leicester suspension, meaning he will be free to play from Thursday.