ze roberto invited fabiana to the NT when she was just 17/18 yrs old though, same with thaisa. regla torres of cuba won her first olympic gold medal at the age of 17 as well. it all boils down w/c players would show up and step up next superliga.
age is just one part of the equation.
That was ages ago though, he's been far more conservative in regards to who he calls to the team since then. Would I like to see some 18yo like Tainara, Diana or Glayce explode in the club season and join the NT right away? Absolutely. But right now I don't see it happening. And truth be told, I'd rather have players like Rosamaria, Drussyla, Bia and Gabi improve even more than have new ones come and risk hindering their development.