The two sides last met in the Gold Coast last October in the HSBC Sevens World Series where the Blitzbokke prevailed 28-21. With key playmaker Lee Williams and try scoring machines Chris Knight and Alex Webber unavailable due to injury, Wales will have to be at their best to reach the quarter-finals as Kenya and Canada along with South Africa provide Williams a baptism of fire in his first tournament as head honcho since taking over from Paul John.
"It's quite a physical group, first day's going to be interesting but it's a challenge the boys are quietly excited about and they've trained well over the fortnight and hopefully that's enough to get through a very tough group," he said.
"South Africa are coming off a tournament win, they are the form side in the series, they offer a huge physicality but with a cutting edge; Kenya - you just know the physicality they will bring and we've got to match that, try and pressurise them when they've got the ball and respect the ball when we've got it; Canada, we're always in tough battles with them, came off second best in the Gold Coast but had an excellent win in PE, so a very physical weekend, no doubts about that, but we know what we want to achieve in every facet of the game."
With Paul John moving to Cardiff Blues as backs coach, Williams has been given the next two tournaments in Las Vegas and Wellington to cement his role as head coach - it's a challenge he is taking head on.
"It's a great opportunity for Paul [John] and I'm just fortunate I've been given the chance for Las Vegas and Wellington to lead the team. I've been assistant coach now for five and a half years so I feel more than ready for the challenge.
"There's a huge excitement and some nervousness as well, which is part of the reason why I enjoy coaching. It'll be great to get the boys out there after the amount of work we've put in and see how they do respond."
Wales Sevens squad for Las Vegas:
Adam Thomas (Pontypridd - Captain)
*Dylan Morgans (Carmarthen Quins)
James Davies (Carmarthen Quins)
Sam Cross (Cardiff Met)
Jason Harries (Carmarthen Quins)
Rhys Shellard (Pontypridd)
Rhodri Davies (Llandovery)
Rhys Jones (Cross Keys)
Will Thomas (Cardiff)
Will Price (Aberavon)
Ashley Evans (Bridgend)
Luke Morgan (Bridgend)