Tonga's 36-0 win over Lebanon kept them unbeaten after two rounds of the Rugby League World Cup, with Sione Katoa scoring both the opening and closing tries.
Katoa crossed in the 13th and 79th minutes, while co-captain Addin Fonua-Blake started at prop and helped lead Tonga's forward effort.
Australia beat Fiji 36-22, with Blayke Brailey making his Test debut at hooker as Kangaroo #866.
The Sharks co-captain, who toured with Australia a year earlier without playing, helped create Tom Trbojevic's second-half try and won the penalty that restored Australia's lead in the 55th minute.
New Zealand defeated the Cook Islands 82-16, led by Ronaldo Mulitalo's two tries and 208 run metres, the most by any Kiwi.
Briton Nikora was named on the interchange but did not play.
Cook Islands captain KL Iro saw his side lead 16-12 before New Zealand pulled away; he later described the match as a valuable test for its young players.
Lebanon centre Michael Gabrael faced Sharks 2026 clubmates Katoa and Fonua-Blake, then shared a post-match hug with them after Lebanon's defeat.
Australia have secured a semi-final place, while Tonga and New Zealand will contest a place in the final four in Round 3.
Australia play the Cook Islands on 31 October at Queensland Country Bank Stadium, with Brailey and Iro involved; New Zealand meet Fiji at Cbus Super Stadium, featuring Mulitalo and Nikora.
Tonga face Samoa at CommBank Stadium on 1 November, with Katoa and Fonua-Blake, while Lebanon meet France there with Gabrael.
All matches are live and free on Seven and 7plus Sport.