Saracens wing Chris Ashton has rejected an England Saxons call-up after being left out of the senior tour to Australia this summer.
New Wasps signing Danny Cipriani is one of seven full-capped players selected for the tour to South Africa.
Head coach Ali Hepher has picked a 27-man squad for two games against South Africa A.
"The squad has a good mixture of experienced players and emerging talent," said Hepher.
Wasps wing Christian Wade, Gloucester's Matt Kvesic, Northampton's Luther Burrell and Kieran Brookes, and Bath's Dave Attwood and Semesa Rokoduguni are the other players with Test experience.
"It is an incredibly exciting opportunity for the players and management to prove themselves," Hepher added.
Ashton, 29, helped Saracens win the European Champions Cup and reach the Premiership final but was omitted from the 32-man England squad that will play three Tests against the Wallabies next month.
He missed this year's Six Nations, which England won under new boss Eddie Jones, after being given a 10-week ban for making contact with the eyes of Ulster's Luke Marshall during a European Champions Cup game.
Jones feels Harlequins star Marland Yarde is a "better fit" and has said Ashton needs to "fix" certain parts of his game.
Ashton was given a place in the Saxons squad before he decided not to accept it.
Monday's Saxons squad announcement came a day after Cipriani also failed to make the senior tour.
The 28-year-old missed out to Owen Farrell and George Ford for a place at the Rugby World Cup last year under Stuart Lancaster but took part in an England squad training session in Brighton last week.
With Saracens and Exeter players involved in Saturday's Premiership final, Jones needed to supplement his squad for Sunday's friendly against Wales at Twickenham.
Several of the Saxons squad - Attwood, Kvesic, Burrell, Wasps forward Tommy Taylor and Bath centre Oliver Devoto - will plug the gaps.
Exeter assistant coach Hepher will be assisted by Alan Dickens (Northampton Saints) and Andy Titterrell (Wasps) for the two games in Bloemfontein on 10 June and Outeniqua Park in George on 17 June.
Capped players in the Saxons party
Bath: Dave Attwood (22 caps), Semesa Rokoduguni (1 cap)
Gloucester: Matt Kvesic (2 caps)
Northampton Saints: Kieran Brookes (16 caps), Luther Burrell (13 caps)
Wasps: Danny Cipriani (14 caps), Christian Wade (1 cap)
The full Saxons squad
Ross Harrison (Sale Sharks), Alec Hepburn (Exeter Chiefs), Tommy Taylor (Wasps), George McGuigan (Newcastle Falcons), Jake Cooper-Woolley (Wasps), Kieran Brookes (Northampton Saints), James Craig (Northampton Saints), Mitch Lees (Exeter Chiefs), Charlie Ewels (Bath), Dave Attwood (Bath), Dave Ewers (Exeter Chiefs), Donovan Armand (Exeter Chiefs), Matt Kvesic (Gloucester), James Chisholm (Harlequins), Sam Jones (Wasps).
Dan Robson (Wasps), Michael Young (Newcastle Falcons), Oliver Devoto (Bath), Danny Cipriani (Wasps), Christian Wade (Wasps), Semesa Rokoduguni (Bath), Sam Hill (Exeter Chiefs), Nick Tompkins (Saracens), Luther Burrell (Northampton Saints), Alex Lewington (London Irish), Sam James (Sale Sharks), Mike Haley (Sale Sharks).
Head coach: Ali Hepher (Exeter Chiefs)
Assistant coach: Andy Titterrell (Wasps)
Assistant coach: Alan Dickens (Northampton Saints)
Team manager: Richard Hill