Cape Town - Wales winger George North showed no adverse reaction after suffering a head injury in the team's 21-16 defeat by England in the Six Nations opener in Cardiff on Friday.
"He (North) passed head injury protocol tests that were carried out in the medical room in addition to an on pitch assessment," the Welsh Rugby Union said in a statement on Saturday.
"He also showed no signs and symptoms when follow up tests were carried out immediately after the game."
North left the field for eight minutes during the first half but returned to the fray, missing a tackle on England centre Jonathan Joseph before he crossed for his team's second try.
Prop Samson Lee suffered a concussion and will make a graduated return to training, flyhalf Dan Biggar sustained a cut head and fullback Leigh Halfpenny a minor neck injury.
All four players are expected to be fit for next Sunday's match against Scotland in Edinburgh.