US, South Africa through to final 8 at Vancouver Sevens

United States' Martin Iosefo (12) vies for the ball against Canada's Andrew Coe, right, and Josiah Morra, back, during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)

Canada's Brennig Prevost, left, is tackled by United States' David Still, front right, and Joe Schroeder during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)

South Africa's Sakoyisa Makata, right, gets his hand to the face of teammate Christie Grobbelaar, back, as they tackle Kenya's Alvin Otieno during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)

Kenya's Levy Amunga, left, and South Africa's Darren Adonis vie for the ball during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)

South Africa's Dewald Human, left, tackles Kenya's Harold Anduvate during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)

United States' Martin Iosefo, right, leaps past Canada's Andrew Coe and runs the ball for a try during an HSBC Canada Sevens rugby game in Vancouver, British Columbia, Saturday, Sept. 18, 2021. (Darryl Dyck/The Canadian Press via AP)