"We have Scotland in Scotland with their top side, with a lot of players from the Six Nations, who will be tough. Canada will be really tough, so there are no easy games for us and it is so easy to trip up if you are not up for it."
Tietjens, who has coached teams to four consecutive Commonwealth Games gold medal wins, ended up with just one Super Rugby player in Blues midfielder Pita Ahki in his squad.
"An expression of interest went out to all the players in the franchises to be considered," Tietjens said.
"Pita came to the trials and he performed really well. He became a real contender but since then he has played his way into the starting line-up with the Blues and if they had won last week, he probably would not have come to us."
Tietjens is happy with preparation ahead of the Glasgow games, despite limited time together at Mount Maunganui.
"We had a pretty good year in terms of the world series so I think it is great rewarding these players that have done particularly well to go to the games. It is tough when you can't pick a Tomasi Cama or Lote Rakabula, who have been stalwarts of the team over a number of years."
Tietjens confirmed any player who wants to represent the All Blacks Sevens at the 2016 Olympic Games will have to make themselves available after next year's Rugby World Cup and play the whole IRB Sevens World Series to be considered.
Even if that means missing All Blacks tests.
"It will be a big call, but that's the way it has to go," he said.
