Durban - Lock Joe Launchbury has given England a fitness scare ahead of the first Test against South Africa in Johannesburg Saturday.
The Wasps forward nursed a calf injury during training Tuesday in Durban, where England will be based during the three-international series against the Springboks.
Launchbury, who has been capped 52 times, underwent a fitness test watched by the England physiotherapists.
"Joe has just got a small niggle on his calf and we will see where he gets to with that," scrum coach Neal Hatley told reporters.
"It is hard to tell how much of a doubt he is for the Johannesburg Test - we will have a look at what he has done today."
If the 27-year-old lock is ruled out of the Ellis Park Test, England coach Eddie Jones could select an all-Saracens second row of Maro Itoje and Nick Isiekwe.
"Other than Joe everyone is fit and ready to go," added Hatley as England seek to win a series in South Africa for the first time.
The Springboks have won three of the previous five multi-Test tours by England and drawn the other two, winning eight internationals, drawing one and losing two.
After the Johannesburg Test, the countries clash in Bloemfontein on June 16 and in Cape Town on June 23.