Craig Dowd's All Blacks Rugby World Cup squad

A lack of game time this season sees Sonny Bill Williams miss Craig Dowd's World Cup squad Hagen Hopkins/Getty Images

With the playoff stage upon us in Super Rugby, it is a chance to reflect on the regular season and look at the prospective All Blacks squad to contest the Rugby World Cup later this year.

The Rugby Championship will be played beforehand, but based on the form seen in Super Rugby my All Blacks squad for Japan would not feature midfielders Sonny Bill Williams or Ma'a Nonu. That's probably the main talking point in my 31-man touring party.

The main reason for not including Williams would be that he simply hasn't played enough rugby this season due to injury. Furthermore, there have been some players in his position who have been playing some seriously good rugby; if we're being honest, those players deserve strong consideration.

Williams is 33 and he might be just running out of time.

Nonu, meanwhile, came into the mix with some outstanding play this season. But by going overseas he's ruled himself out.

Another key factor in my thinking is the choice of Brad Weber as the third halfback. Weber heads Te Toiroa Tahuriorangi simply because he's had a sensational season with the Chiefs and maintained the starting spot in that side.

I've also gone for Luke Jacobson on the blindside flank. He adds some fresh blood to the pack, plays exciting rugby and is getting better; he will wear an All Blacks jersey, it is just a matter of when. Form is just that little bit more important in a World Cup year; Vaea Fifita, Jackson Hemopo and Akira Ioane have had their moments but I believe Jacobson has got more of a future in the black jersey.

Like Weber, Jacobson has really been in superb form.

In the backs, I would take Braydon Ennor because of his ability to cover centre and wing. With Ben Smith, Jordie Barrett and David Havili among my outside backs, George Bridge scrapes into the final spot.

Havili also has the ability, along with Barrett, of being able to play in the midfield, so their case is even stronger. Versatility is crucial in a squad environment; I think Ennor is a nice fit and covers those selection options.

Will Jordan, providing he has recovered from his injury, is in my back-up list alongside the likes of Waisake Naholo, Tevita Li, Nehe Milner-Skudder, Wes Goosen and Sevu Reece.

Reece, who is likely to be the highest try-scorer in Super Rugby for 2019, wouldn't look out of place in the side; but I'm certain his time will come in the future.

As for the rest of the squad, I think the trend has been to not stray too far from those selections made in previous years. Rather than taking any risks or gambles, the All Blacks tend to stick with the tried and tested.

Up front, among the props, I think Angus Ta'avao is close, and pushing hard but the four chosen are all fit again. Joe Moody and Owen Franks are very experienced, while Karl Tu'inukuafe and Ofa Tu'ungafasi have been the back-up props through the past two seasons.

The three hookers are steady as ships so nothing changes there.

I went with three locks in Brodie Retallick, Sam Whitelock and Scott Barrett. That leaves Patrick Tuipulotu in the standby category but Liam Squire and Shannon Frizell could, if need be, cover the second-row, too.

Among the loose forwards, if anything happens to Kieran Read at No. 8 then both Squire and Ardie Savea offer different options depending on who you might be playing.

My selection has been based on taking into consideration the inevitable injuries that will occur at some stage, and pool games where you will need to rest players. By having versatility within the squad you can have guys cover key positions.

Across my selections you can see the rewards for the Crusaders, who have 11 players. That includes the midfield combination of Ryan Crotty and Jack Goodhue: They have formed an excellent partnership there for the Crusaders and you would want to retain that in Test rugby.

I've gone for two first five-eighths; they're going to be involved in most games. I don't think you can afford to take three first-fives to a World Cup and someone like Josh Ioane would be in the standby corner.

Given the Crusaders and Hurricanes are likely to be involved in the Super Rugby semi-finals, at least, Ioane may be given a taste of All Blacks experience when in Argentina during the Rugby Championship. Either Richie Mo'unga or Beauden Barrett could be spared from that trip as Steve Hansen has said some players involved in the final will not be considered.

That would allow Ioane to be up with the play in the All Blacks environment and ready to be called up in an emergency. But it would not be at the cost of more versatility elsewhere in the backline come the World Cup.

Craig Dowd's New Zealand World Cup squad:

Props: Karl Tu'inukuafe, Ofa Tu'ungafasi, Joe Moody, Owen Franks;

Hookers: Nathan Harris, Codie Taylor, Dane Coles;

Locks: Brodie Retallick, Scott Barrett, Sam Whitelock

Back-rowers: Sam Cane, Ardie Savea, Luke Jacobson, Shannon Frizell, Liam Squire, Kieran Read

Half-backs: Brad Weber, Aaron Smith, TJ Perenara

Fly-halves: Richie Mo'unga, Beauden Barrett

Midfielders: Anton Lienert-Brown, Ryan Crotty, Jack Goodhue, Ngani Laumape

Outside backs: Rieko Ioane, Braydon Ennor, George Bridge, David Havili, Ben Smith, Jordie Barrett.