21-year-old Saracens prop Mako Vunipola is expected to be included in the England squad for the November internationals to be named on Thursday.
The 130 kg, New Zealand-born son of former Tonga international Fe'ao Vunipola, has widely been touted as the likely replacement for Alex Corbisiero, who is not due to return to action from a knee injury until mid-November.
On Thursday England coach Stuart Lancaster will also announce replacements for Ben Foden, Tom Croft and Rob Webber, who have all been ruled out of the Tests against Fiji, Australia, South Africa and New Zealand.
Saracens director of rugby Mark McCall believes Vunipola is ready to make the step up to Test rugby having already played for England U18s and the U20s although he missed the whole of last season through injury.
"He has risen to every challenge he has had so far," said McCall.
"He has played some big games for us and is an outstanding young talent.
"Corbisiero's injury opens the door for Mako. But Mako is more than ready, he is as good a rugby-playing loosehead as I have come across."