South Africa flanker Roelof Smit has been ruled out of the rest of their European tour after he was injured in training.
The 23-year-old suffered a suspected torn bicep after attempting a tackle during the Springboks' training session in London on Monday morning.
The latest blow comes after Jesse Kriel was ruled out of the three Test Matches against England, Italy and Wales after he sustained a leg injury during Saturday's 31-31 Wembley draw with the Barbarians.
Kriel has been replaced by Rohan Janse van Rensburg for the remainder of the tour and coach Allister Coetzee has called up Uzair Cassiem as a replacement for Smit.
Coetzee is under pressure following South Africa's recent poor run of results, including a record 57-15 defeat by New Zealand last month.
They needed two late tries to force a draw with the Barbarians and will be big underdogs when they take on England at Twickenham this weekend.
However, Coetzee has been able to welcome a host of his more experienced players such as JP Petersen, Bryan Habana and Warren Whiteley, who joined up with the squad on Sunday night
He said: "A week is a long time in rugby. We feel like we started last night, we had a full complement of the Springboks team at our first team meeting.
"You get the feeling it's a big week, the start of the so-called official tour. We are raring to go.
"We are definitely the underdogs, we are playing the second-best team in the world who are on a 10-game winning streak. They won all three Tests in Australia so there is a lot of confidence in the English side.
"For every team the belief comes with a win, one win, and that is what we are looking for, that performance.
"History can't help us on Saturday but you can be sure the boys will be up for this one."
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