Samoa's Uale Mai and Springbok Sevens star Cecil Afrika are both surprise call-ups for this weekend's USA Sevens, the fourth event in the HSBC Sevens World Series, to be played at the Sam Boyd Stadium in Las Vegas on 12-13 February.

Defending World Series champions Samoa have flown in Spain-based Mai as cover for captain Lolo Lui, who is suspended and will play no part in Las Vegas.

Afrika's inclusion in the same pool is a major boost for the South Africa squad. Their outstanding player in the first two tournaments, he scored 17 tries and is still joint top in the try-scoring charts, despite having played no part in Wellington last weekend. He joins Neil Powell in flying out for this USA event.

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New Zealand suffered a major blow on home soil in Wellington when their captain DJ Forbes sustained an injury in the final against England. Forbes has been replaced in their squad by newcomer Rory Grice.

England also suffered a body blow in Wellington, losing their outstanding Fijian-born forward Isoa Damu, who injured his shoulder. Damu has been replaced in England's squad by Sevens World Series debutant Mark Odejobi.

For Fiji, Waqa Kotobalavu and Nikola Matawalu come in to replace Semesa Gonevou and Apisai Navuoro. In the same pool Australia, Canada and Scotland also make changes. Zack Holmes has flown in for Australia as a replacement for hulking forward Henry Vanderglas, while Canada have called up Matt Evans and Justin Mensah-Coker to replace Keaton Styles and Beau Parker. For Scotland Graham Fisken replaces David McCall.

For Kenya, Lavin Asego and Lawrence Buyachi come in for Brian Nyikuli and Wilson Opondo and in the same pool Wales call up Mathew Morgan in the place of Ricky Thomas.

The three sides not to have played in Wellington name 18 World Series debutants between them. Caribbean champions Guyana name four newcomers, while Asia's number one side Japan and South American qualifiers Uruguay name six and eight respectively.

Of the other squads who competed in New Zealand last weekend, this week's hosts USA, Argentina and France are unchanged for Las Vegas.

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