Sevens debuts at the Olympics in 2016 and High Performance Sport New Zealand has already indicated it will receive extra funding over the next few years.
Tietjens' trial squad includes secondary school stars Lolagi Visinia, Ardie Savea, Joe Webber and Mark Jackman, although he admitted some of the trialists might be daunted about what the next few days will bring.
"It's great to see these young kids coming through but I think for some of them, the prospect of coming to a sevens trial can be quite intimidating, although I know a couple of them are really looking forward to it.
"It's an exciting time to be involved with sevens if you're a talented young player coming into this trial wanting to put up your hand as an Olympic medal hopeful in four years."
The Condor sevens secondary schools tournament team will train with the side at Blake Park today.
Tietjens has lost three players from his original trial squad, with Auckland's Nathan Hughes ruled ineligible, Counties Manukau's Ahsee Tuala withdrawing to focus on playing for Samoa and Frank Halai attending a family funeral.
A national contracted squad of 15 will be named on Friday at the conclusion of the trial and will assemble in Wellington next Thursday ahead of the Wellington tournament on February 3-4.
New Zealand sevens trialists: Toby Arnold (Bay of Plenty), Tomasi Cama (Manawatu), Shane Christie (Tasman), Rob Thompson (Manawatu), Frazier Climo (Taranaki), Scott Curry (Bay of Plenty), Matt Faddes (Otago), DJ Forbes (Counties Manukau), Frank Halai (Waikato), Bryce Heem (Auckland), Joe Hill (Otago), Mark Jackman (Canterbury), Solomon King (North Harbour), Warwick Lahmert (Taranaki), James Lowe (Tasman), Jono Malo (Waikato), Tim Mikkelson (Waikato), Kieran Moffat (Otago), Waisake Naholo (Taranaki), Kylem O'Donnell (Taranaki), Ken Pisi (North Harbour), Charles Piutau (Auckland), Lote Raikabula (Wellington), Glen Robertson (Waikato), Ardie Savea (Wellington), Ben Souness (Taranaki), Nafi Tuitavake (Harbour), Lolagi Visinia (Auckland), Joe Webber (Waikato), Jack Wilson (Bay of Plenty).