Ben Youngs was stretchered off as England beat Italy 46-15 in their opening Six Nations game.
With only one other scrum-half in the squad, Eddie Jones will call-up another nine to join Danny Care in the group.
RUCK POLL
DAN ROBSON
The 25-year-old enjoyed an eye-catching 2016/17 season as well, playing a 30 times for Wasps and scoring nine tries. Will Greenwood was one of many to be perplexed when Jones yet again snubbed the playmaker for the initial squad. By far the best uncapped English scrum-half in the game today.
RICHARD WIGGLESWORTH
A master of the box-kick, Wigglesworth is one of the true stalwarts of the Saracens side, making over 180 appearances for the club from scrum-half. The 34-year-old, who has won 27 caps, may not be a long-term replacement, but his experience could be a key factor to why he might get the call.
BEN VELLACOTT
Gloucestershire Live understands that Vellacott is part of the Elite Player Squad (EPS) and Jones has previously said that he rates the Gloucester Rugby youngster.
JACK MAUNDER
Won his first England cap against Argentina last summer and impressed in the Anglo Welsh Cup over the weekend, scoring a try in Exeter’s 43-20 win against Saracens. AN outsider, but obviously someone that Jones rares.