Penrith back-rower James Fisher-Harris is one of eight additions to the Kiwis train-on squad for the upcoming test against Australia in Perth and subsequent Four Nations tournament in England, while Warriors prop Ben Matulino has withdrawn from contention to have surgery.
Fisher-Harris enjoyed a break-through season with the Panthers, with his rugged defence and aggressive running helping him to cement a first grade spot.
The 20-year-old former Junior Kiwis representative, together with club teammates Dallin Watene-Zelezniak, Suaia Matagi and Te Maire Martin, were ushered into the national squad after Penrith's NRL title run ended with last week's 22-12 semi-final defeat to Canberra.
After two false starts due to injury and suspension, Watene-Zelezniak finally made his Kiwis debut in May's transtasman test defeat to Australia in Newcastle, while Matagi featured in the triumphant 2014 Four Nations campaign, coming off the bench against Samoa.
Martin's inclusion comes after he impressed in six first grade appearances before a shoulder injury suffered in Penrith's round eight loss to Cronulla saw the 20-year-old playmaker miss the Panthers run to the playoffs.
Joining them in the wider squad are Brisbane trio Adam Blair, Alex Glenn and Jordan Kahu, after the Broncos premiership hopes were dashed in last week's 26-20 semi-final loss to the North Queensland Cowboys.
All three were named for the May test against Australia, but Glenn withdrew with a calf injury. Blair co-captained the Kiwis in their two-one series loss to England last year and Kahu's versatility has proven valuable since debuting on that same tour.
Meanwhile, Matulino has withdrawn from the squad and it is understood he requires minor surgery to fix lingering knee and shoulder injuries.
New Kiwis coach David Kidwell has added rookie Warriors hooker and back-rower Jazz Tevaga to the extended group.
The latest additions bring the current squad to 31, with more to come after next weekend's NRL preliminary-finals.
The final touring squad of 24 will be named during the week after the NRL Premiership grand final on October 2.
The Kiwis face Australia at Nib Stadium on October 15 and kick off their Four Nations title defence against hosts England in Huddersfield on October 29.
Kiwis train-on squad: Adam Blair, Lewis Brown, Greg Eastwood, James Fisher-Harris, Addin Fonua-Blake, David Fusitu'a, Alex Glenn, Shaun Johnson, Jordan Kahu, Solomone Kata, Shaun Kenny-Dowall, Thomas Leuluai, Sam Lisone, Isaac Liu, Tuimoala Lolohea, Issac Luke, Simon Mannering, Te Maire Martin, Suaia Matagi, Manu Ma'u, Sam Moa, Jason Nightingale, Tim Simona, Brad Takairangi, Martin Taupau, Elijah Taylor, Jazz Tevaga, Bodene Thompson, Manu Vatuvei, Jared Waerea-Hargreaves, Dallin Watene-Zelezniak.