"We have a range of midfield players around the country at the moment who offer a range of different skills," says All Black assistant coach Ian Foster. "There is Robbie Fruean at the Crusaders who is enormously powerful and Francis Saili has played very well for the Blues. Ryan Crotty and Tim Bateman had good Super Rugby campaigns.
"Often there is one young player coming through who is head and shoulders above his peers and you can see that he's got potential to develop into an international player.
"We are looking at our young midfielders and asking who can we develop into an international player?
"I guess that's the message - we would like to be forced into picking someone; someone to really come through strongly and state their case."
Williams' departure will leave Nonu as the only out-and-out, line-breaking, direct option at second five. Controlling the gain line and being able to blast over it in the midfield is deemed critical in test rugby. But Foster says that doesn't necessarily mean the coaches will restrict themselves to power players.
"We definitely see a role for the ball-playing No12 - someone who can act as a second receiver. The ultimate scenario is probably to have one each so we can have a direct option and a ball-playing option.
"I think also that while taking the gain line is important, Tamati and Conrad have shown there are other ways to win it. Those two were among the most effective at getting over the gainline during Super Rugby, so timing, footwork and angles of attack are just as important."
It's those qualities Foster mentions that are drawing the panel towards Ben Smith as a longer-term option in the midfield - and more specifically at centre. The Highlanders utility has predominantly played fullback and wing with occasional ITM Cup and Super Rugby outings at second five. Foster, though, sees similarities between Ben Smith and Conrad Smith and is interested to see how the former would cope at centre in an international game.
Opportunities to do that will be limited but, depending on how games develop during the Rugby Championship, Smith may be injected at centre off the bench. It's more likely that the end-of-year tour will be viewed as a better opportunity to try out Smith in that role, with tests against Scotland and Italy providing the chance for the selectors to be a little more experimental.