The 17-year-old triumphed in the women's vault at the Cairo International Stadium with an average of 13.983, beating the 13.600 from Italy's Asia D'Amato and 13.599 by Panama's Hillary Heron.

Roberson also saw off a challenge from an Italian gymnast in Alice D'Amato to win floor exercise gold, scoring 13.700 to beat her closest challenger by 0.200 and Indonesia's Rifda Irfanaluthfi with 12.633.

The American additionally took a silver on the balance beam with 13.233, the event won by Italy's Giorgia Villa who notched 13.600.

D'Amato was a second Italian winner, leading a one-two with Villa on the uneven bars courtesy of scores of 14.633 and 14.200 respectively.

Belgium's Erika Pinxten earned uneven bars and balance beam bronze.

Kovtun triumphed on the parallel bars for the third time from four World Cups this year, the reigning European champion notching 14.833 to beat the 14.066 from home favourite Mohamed Afify.

He upgraded a silver in the floor exercise from the last stop in Azerbaijan's capital Baku to triumph with 14.433, overcoming challenges from Croatia's Aurel Benović and Ireland's Eamon Montgomery who posted scores of 14.166 and 14.066 respectively.

The horizontal bar provided a third win in Cairo for Kovtun as he scored 14.100 to beat the 13.766 from Belgium's Maxime Gentges and 13.533 from The Netherlands' Casimir Schmidt.

Kovtun shared a bronze with Armenia's World Championships bronze medallist Harutyun Merdinyan on the pommel horse, with Chinese Taipei's Olympic silver medallist Lee Chih-kai triumphing on 15.033 and Gagik Khachikyan of Armenia placing second with 14.733.

Artur Davtyan of Armenia earned his third vault World Cup win of the year with an average of 15.116, Ukraine's Nazar Chepurnyi taking silver with 14.799 and Czech Republic's Ondrej Kalny bronze with 14.333.

Azerbaijan's Nikita Simonov was the other winner from the World Cup, scoring 14.966 to the 14.700 of Italy's Salvatore Maresca and 14.666 of Armenia's Artur Avetisyan.