Cape Town - The United States have stunned the Blitzboks at the London Sevens, running out to an emphatic 24-12 victory in their Pool A encounter.
Tries from Ruhan Nel and Siviwe Soyizwapi were not enough to see the World Rugby Sevens series champions to their third victory on the day.
The United States scored four excellent tries through Stephen Tomasin, Ben Pinkelman, speedster Perry Baker and Andrew Durutalo.
Madison Hughes added two conversions.
The Blitzboks finish the pool in second place and will contest the quarter-finals on Sunday where they will face England at 12:42 (SA time).
Earlier, the Blitzboks beat both Kenya (12-10) and Wales (12-10) in their first two pool encounters.