Saracens lock Maro Itoje will travel with the England squad to Edinburgh ahead of Saturday's Six Nations opener against Scotland at Murrayfield.
Itoje was omitted from the original 23-man squad by new England coach Eddie Jones, but he has been added to the travelling party as cover for Courtney Lawes, who has to prove his fitness following a hamstring injury.
Wasps back Elliott Daly, who like Itoje is uncapped, will also head to Scotland as a reserve.
Jones, who will name his team on Thursday, said he felt that Itoje still had elements of his game that needed work when he left the 21-year-old out initially.
However, the Australian was present at Allianz Park on Saturday to see Itoje's man-of-the-match performance in Sarries' 19-13 defeat of Bath, describing it as his finest game for the Aviva Premiership champions.
"Courtney is progressing. We'll give him until Thursday. It looks pretty positive. He probably won't train until Thursday but we're hopeful he'll be all right," Jones said on Monday.
"I went to Saracens - I hid in the stands - and it was the best game I've seen Itoje play for them. It was really good, very impressive.
"It's never too late to get in the 23. The 23 isn't set in stone, but generally speaking the 23 that we kept are the front-runners. Now they can play themselves out of selection by injury and by attitude, so there are still opportunities."
Forwards coach Steve Borthwick believes Itoje will become a key player for England.
"Hopefully he has a huge future in front of him," Borthwick said. "He has shown the potential he has and our job now is to help him develop and learn so that he can be an international for England for a long time.
"He's a young guy and now that he's spending time around the squad, hopefully it will lay the foundation for an England career that will last a lot of years.
"We don't need to be rushing him, we just need to make sure that he's absolutely ready to go.
"Being able to play six and second row is helpful in many ways and it will be interesting to see how he develops.
"He certainly has the athleticism to operate at six and that's a huge asset for him."