Up front, Emblen can run a largely first-choice All Whites strike-force with Smeltz, Chris Wood, Kosta Barbarouses and Marco Rojas and Nelsen, Tommy Smith and McGlinchey are also automatic choices in Ricki Herbert's starting XI.
Adam Thomas (Waikato FC), Alex Feneridis (Auckland City), James Musa (Team Wellington) and Dakota Lucas (Team Wellington) are the only players other than O'Keefe who haven't appeared for the All Whites but Thomas, Musa and Lucas went to last year's Under-20 World Cup in Colombia and Feneridis has been to two Club World Cups.
"It's brilliant to have so many All Whites," Emblen said. "I hope we can boast the most internationally capped players of any side at the Olympics but we are a unique country because there's not the pool of players everybody else has to choose from.
"Our players get opportunities quicker than if they were playing for another nation.
"Look at Tim Payne. He's played for New Zealand under-17s, 20s, 23s and All Whites in a year. That wouldn't happen in many other nations no matter how good the player is.
"We have to use that to our advantage."
NEW ZEALAND SQUAD
Goalkeepers: Jake Gleeson, Michael O'Keefe
Defenders: Ian Hogg, Tim Myers, Tommy Smith, Ryan Nelsen* (c), Adam Thomas, James Musa
Midfielders: Tim Payne, Michael McGlinchey*, Alex Feneridis, Cameron Howieson, Adam McGeorge
Forwards: Kosta Barbarouses, Shane Smeltz*, Chris Wood, Marco Rojas, Dakota Lucas
*Denotes over-age players