The Fijians batted first and after 19.2 overs were reeling at 5-42. Wickets continued to fall and they found themselves all out for 88 inside 36 overs.
Jack Fraser Charters (16) and Samuel Nakuna (16) top scored with the bat. With the ball for Garamuts, it was Boge Daniel Arua (4/21) who did the damage.
Despite their losing their openers cheaply, Heagi Ronald Toua (27), Vagi Karaho (15) and Nou Reva Rarua (14*) guided the Garamuts home to reach the target in 25.2 overs losing six wickets along the way.
PNG will take on hosts Samoa tomorrow.