In 2018, Marcus was named captain of the Tongan National Basketball Team. He helped lead Tonga to their first bronze medal in history at the FIBA Polynesian Cup where he averaged a tournament best 39.2 points per games, including a historic best 55-point game in the elimination game against the Cook Islands. Alipate earned himself to the FIBA All-Star 5 team, and helping Tonga punch their ticket to the Pacific Games in Apia, Samoa. Also during 2018, Marcus signed with the Geraldton Buccaneers in Australia.
At the 2019 Pacific Games in Samoa, Marcus led the pre-olympic qualifier again with 34.3 points per game, including a tournament best with 44 points against New Caledonia. Alipate was named to the FIBA All-Star 5.
In 2022, Alipate led Tonga to its first ever silver medal at the FIBA Polynesian Cup in New Zealand, punching their ticket to the 2023 Pacific Games in the Solomon Islands. He was named to the FIBA All-Star 5. Also in 2022, Marcus was named to the inaugural 3x3 team that competed at the 2022 Asia Cup in Singapore.