Ireland, Wales and England are New Zealand's biggest challengers for the Rugby World Cup title, while Scotland "could throw a spanner in the works", and France and Argentina are underdogs for the Sept 20-Nov 2 event in Japan.
While former All Blacks half-back and fly-half Piri Weepu says the 2011 and 2015 champions New Zealand are the favourites to lift their third straight world title this year, the 35-year-old is cautious about the chasing teams this year.
"There're so many teams that have developed their skill sets and their game, their rugby brain, and their rugby nous on and off the field," said Weepu, who is in town to promote the April 13-14 HSBC Singapore Rugby Sevens.
"We have lost twice to Ireland (in 2016 and 2018). Wales have just won the Six Nations, they could carry on that momentum and turn some heads. They are improving every year and they are not far off.
"England are off and on but they are there or thereabouts. They have got a good squad and a great coach. He (Eddie Jones) might talk a lot of rubbish at times but... is probably doing it because he believes his players are good enough," added the 2011 World Cup winner, who also tipped hosts Japan to make their first knockout phase.
But New Zealand should pay attention first to progressing from Pool B after being drawn alongside 1995 and 2007 champions South Africa, Italy, Namibia and Canada.
Catch S'pore 7s
Tickets for the HSBC Singapore Rugby Sevens are available and on sale from $19. Family packages and premium tickets can be purchased via the Singapore 7s website www.singapore7s. sg or www.sportshubtix.sg, hotline at 3158-7888, Sports Hub Tix box office at the Singapore Indoor Stadium, The Star Performing Arts Centre box office, Scotts Square concierge desk, and all SingPost outlets.
Icons Huriana Manuel, Waisale Serevi and D.J. Forbes will be back to engage with locals, while the HSBC Hot Seat returns for the fourth year in a row along with a best dressed contest for all ticket holders in the stadium.
Minions characters by Illumination will also be making appearances, along with the Dreamworks All Stars during the week, at meet and greets at the Fun Zone.
He said of South Africa: "They put a lot on pressure against the All Blacks last year in the Rugby Championship. They won 36-34 in Wellington and almost won again in Pretoria before New Zealand's 32-30 comeback win.
"Every four years, they seem to have something new that they are really strong in. They used to do the Garryowen chase (a very high kick covering a short linear distance which gives the attacking side opportunities), they were really strong in that, and it worked for them.
"They built a lot games around that. At the moment, they have sort of adopted a little bit of that but also being able to apply pressure for 80 minutes, which is exactly what the All Blacks do."
But New Zealand have strengthened their side as well, with Weepu naming 22-year-old winger Rieko Ioane as the player to watch, and locks Sam Whitelock and Brodie Retallick as the team's leader figures in their title bid.
He added: "What has improved is the skill set of every individual on the field. Everyone understands how each other plays on the field, what they enjoy, like what lines they like running, which guys you can run off if they put you into holes.
"It's just the whole game play and how they are able to manipulate a defence system for 80 minutes. They may not be leading the game at the start, but they always try and make sure they finish strong."
The All Blacks will have extra motivation to retain the title, to lift a nation still reeling from last Friday's mosque shooting in Christchurch.
Wellington native Weepu said: "It's unbelievable that someone would just go out there into a mosque and open fire."