Uncapped Bath hooker Kepu Tuipulotu and Saracens back Noah Caluori were named in Steve Borthwick's England training squad as was newly available South African Benhard Janse van Rensburg ahead of the new Nations Championship on Monday.
With Jamie George, who is also included, retiring after next year's World Cup and Luke Cowan-Dickie injured, 20-year-old Tuipulotu will be challenging Leicester's Jamie Blamire and Saracens' Theo Dan to become England's long-term answer at No 2.
The Bath University student has been used sparingly at Bath Rugby this season but his remarkable speed off the mark, agility and power have long marked him out as a future international, and that time looks to be coming sooner rather than later after he considerably improved his lineout and set-piece work this season.
Spring-heeled Caluori, 19, is top of the Prem try-scoring charts with 18 this season. Borthwick has had him in training groups previously but he did not make any matchday squads.
His Saracens teammate Charlie Bracken, son of former England scrumhalf Kyran, is also included, as is uncapped Northampton scrumhalf Archie McParland. Not included are Bath centres Max Ojomoh and Ollie Lawrence.
Bristol centre Van Rensburg, 29, has become available under the five-year residency rule after the RFU lobbied World Rugby over his eligibility. He previously played one game as a replacement for South Africa's under-20 team.
The squad will assemble on Monday for a three-day camp at England's training base at Pennyhill Park.
They begin their Nations Championship campaign against South Africa in Johannesburg on Saturday, July 4, followed by matches against Fiji and Argentina.
ENGLAND TRAINING SQUAD
Forwards:
Jamie Blamire (Leicester Tigers)
Ollie Chessum (Leicester Tigers)
Arthur Clark (Gloucester Rugby)
Alex Coles (Northampton Saints)
Chandler Cunningham-South (Harlequins)
Tom Curry (Sale Sharks)
Theo Dan (Saracens)
Alex Dombrandt (Harlequins)
Ben Earl (Saracens)
Ellis Genge (Bristol Bears)
Jamie George (Saracens)
Joe Heyes (Leicester Tigers)
Nick Isiekwe (Saracens)
Maro Itoje (Saracens)
Emmanuel Iyogun (Northampton Saints)
George Martin (Leicester Tigers)
Beno Obano (Bath Rugby)
Asher Opoku-Fordjour (Sale Sharks)
Guy Pepper (Bath Rugby)
Henry Pollock (Northampton Saints)
Vilikesa Sela (Bath Rugby)
Kepu Tuipulotu (Bath Rugby)
Backs:
Seb Atkinson (Gloucester Rugby)
Charlie Bracken (Saracens)
Noah Caluori (Saracens)
Fraser Dingwall (Northampton Saints)
Immanuel Feyi-Waboso (Exeter Chiefs)
George Ford (Sale Sharks)
Tommy Freeman (Northampton Saints)
George Furbank (Northampton Saints)
Benhard Janse van Rensburg (Bristol Bears)
Archie McParland (Northampton Saints)
Alex Mitchell (Northampton Saints)
Cadan Murley (Harlequins)
Adam Radwan (Leicester Tigers)
Tom Roebuck (Sale Sharks)
Henry Slade (Exeter Chiefs)
Fin Smith (Northampton Saints)
Marcus Smith (Harlequins)
Ben Spencer (Bath Rugby)
Freddie Steward (Leicester Tigers)
Jack van Poortvliet (Leicester Tigers)
Rehabilitation: Luke Cowan-Dickie (Sale Sharks)
Not considered for selection (injured/unavailable): Fin Baxter (Harlequins), Ben Curry (Sale Sharks), Elliot Daly (Saracens), Trevor Davison (Northampton Saints), Greg Fisilau (Exeter Chiefs), Will Muir (Bath Rugby), Bevan Rodd (Sale Sharks), Sam Underhill (Bath Rugby).