James Mortimer and irbsevens.com 20.Jan.2014Getty Images
Auckland player Akira Ioane has had to withdraw, and has been replaced by Manawatu’s George Tilsley.
Tilsley has previously played for the All Blacks Sevens and was player of the tournament at New Zealand's recent National Sevens.
Another noticeable absentee in Tietjens' side is influential playmaker, Tomasi Cama, who earlier suffered a calf injury in training.
“He (Cama) is certainly the best half back in the world in Sevens and having him injured is a real concern but he will bounce back and at the same time we are building depth," said Tietjens.
"Gillies Kaka I am sure will step up to that role. He was the best player at Rugby World Cup in Russia and we have very capable Mark Jackman as well who can thrive in that position.”
The bad news for the series champions doesn't end there, with Sherwin Stowers and Joe Webber ruled out with injury over the weekend.
Stowers has been replaced by Waisake Naholo, while David Raikuna will cover for Webber.
The All Blacks Sevens, who lead the Series standings after the first three rounds, have not won in Las Vegas in the four years at the Sam Boyd Stadium, the Cup shared between defending champions South Africa (twice) and Samoa.
“We have played consistently well there so it’s not that we don’t play well there, it comes down to those defining moments that decide whether you win or lose," added Tietjens, whose side lost in the Cup final last year.
"We have to use different tactics because there is not as much width on the field so there is a lot more contact and I have picked a side that is very strong and very big and hopefully they can do the work for us.”
New Zealand begin their campaign against Australia, the side they beat to win the opening round of the Series on the Gold Coast, before facing matches against Scotland and the Dubai Sevens champions Fiji.
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