Courtney Lawes will miss England's Test against South Africa on Saturday due to a back injury, forwards coach Steve Borthwick has confirmed.
The Northampton Saints lock sustained the injury earlier this month while sleeping in a hotel bed that was too small for his 6'7" frame.
Lawes left England's training camp in Vilamoura, Portugal to undergo specialist treatment in the UK but has since re-joined the squad.
The 29-year-old is definitely out of this weekend's game against the Springboks but is working to be fit for England's Test against the All Blacks on November 10, live on Sky Sports.
Borthwick told Sky Sports News: "[Lawes] returned to the UK but has come back out to join us. Watching him this morning and speaking with him, he is really, really positive and feels really good.
"So all is very positive there. Whilst not available for this weekend, he will stay with us and continue his return to play which will hopefully be in the very near future."
Asked if Lawes will be back for the New Zealand game, Borthwick replied: "You monitor these things on a daily basis. We have got an excellent strength and conditioning team and a medical team who will work closely with him."
England are already without a host of key forwards for the Quilter Internationals, including Billy and Mako Vunipola, Joe Launchbury, Chris Robshaw and Nathan Hughes.
But Borthwick views it as a valuable opportunity to build depth ahead of the 2019 World Cup and is confident England still have enough quality to compete.
"We clearly have a few players that have been unavailable for selection in the forward pack but what does is it creates great opportunity for other players to come through and we have seen that happen in the past," Borthwick said.
"[Lawes is] an outstanding player [but] we have got lots of options there. We have a lot of strength in depth. We have been building.
"If you look at the second row there, we have got Maro (Itoje), George Kruis, Charlie Ewels and Elliott Stooke.
"We have got a lot of competition in the back row across all three positions."
#Followtherose this autumn with all of England's Tests live on Sky Sports throughout November. The action starts on Saturday, November 3 against South Africa before clashes against New Zealand, Japan and Australia.