The 20-year-old, whose brother Marcus is an established name with the England 7s team, is the only change from the side that started in last week’s 24-21 defeat to New Zealand after Rokoduguni failed to overcome an injury.
Anthony has been pushing hard for a while and has been in impressive form for Bath and in training with us
Watson came off the bench last week to win his maiden cap and has been handed a starting berth ahead of Harlequins winger Marland Yarde, who provides cover from the bench.
“Just being on pitch on Saturday gave me a lot of confidence,” Watson said. “Having a first cap has settled a few things down.
“This weekend it’s going to be about getting out there and letting my attack speak for itself.
“In defence, I have to be assured and confident. I’ll need to stay calm.”
Harlequins scrum-half Danny Care will win his 50th cap as he continues his half-back partnership with Saracens star Owen Farrell.
Northampton Saints duo Dylan Hartley and Courtney Lawes both successfully completed the graduated return to play protocol and keep their places at hooker and lock respectively.
“Anthony has been pushing hard for a while and has been in impressive form for Bath and in training with us,” said England head coach Stuart Lancaster.
“It was great that he got on against New Zealand and we feel he is ready to start.
“Equally, it’s good to have Marland back in the match-day 23.
“Congratulations to Danny Care who will be winning his 50th cap. It’ll be a special moment for him and I am sure he will rise to the occasion.”
England have not beaten the Springboks since Lancaster took charge of the Red Rose in 2012, and their last win over them came in November 2006 as they came from 21-13 down to win 23-21 through an Andy Goode penalty and converted Phil Vickery try with seven minutes remaining.
After a disappointing performance in a 29-15 defeat to Ireland last week, Lancaster expects another tough test against the Springboks this weekend.
“I know the players are looking forward to the challenge,” Lancaster added.
“South Africa have quality and experience across the park and it will be a big test for us.”
England: Mike Brown (Harlequins); Anthony Watson (Bath Rugby), Brad Barritt (Saracens), Kyle Eastmond (Bath), Jonny May (Gloucester Rugby); Owen Farrell (Saracens), Danny Care (Harlequins); Joe Marler (Harlequins), Dylan Hartley (Northampton Saints), David Wilson (Bath), Dave Attwood (Bath), Courtney Lawes (Northampton), Tom Wood (Northampton), Chris Robshaw (Harlequins, captain), Billy Vunipola (Saracens)
Replacements: Rob Webber (Bath), Matt Mullan (Wasps), Kieran Brookes (Newcastle Falcons), George Kruis (Saracens), Ben Morgan (Gloucester); Ben Youngs (Leicester Tigers), George Ford (Bath), Marland Yarde (Harlequins)
South Africa: Willie le Roux (Free State Cheetahs); JP Pietersen (Panasonic Wild Knights), Jan Serfontein (Blue Bulls), Jean de Villiers (Western Province, captain), Bryan Habana (Toulon); Pat Lambie (Sharks), Cobus Reinach (Sharks); Tendai Mtawarira (Sharks), Adriaan Strauss (Cheetahs), Jannie du Plessis (Sharks), Eben Etzebeth (Western Province), Victor Matfield (Bull, vice-captain), Marcell Coetzee (Shartks), Schalk Burger (Suntory Sungoliath), Duane Vermeulen (Western Province).
Replacements: Bismarck du Plessis (Sharks), Trevor Nyakane (Cheetahs), Coenie Oosthuizen (Cheetahs), Bakkies Botha (Toulon), Teboho ‘Oupa’ Mohojé (Cheetahs), Francois Hougaard (Bulls), Handré Pollard (Bulls), Cornal Hendricks (Cheetahs).
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