Australia's 36-22 win over Fiji secured a place in the World Cup semi-finals, with Jacob Preston scoring his first Test try four minutes from full-time.
The 25-year-old Bulldogs back-rower celebrated as his mother, stepfather and partner watched from the stands.
"It was awesome. I don't think we were at the best tonight but we'll take the two points and keep moving forward," he said.
Preston called representing Australia a dream come true, recalling childhood admiration for Kangaroos Darren Lockyer, Billy Slater and Cameron Smith.
He also described playing alongside current teammates Tedesco, Munster and Grant as "super special".
Although Preston missed the NRL finals, he has looked at home during the first two World Cup rounds.
After playing 53 minutes off the bench against Fiji, he hopes to start against Cook Islands in Townsville on Saturday.
He praised Fiji's performance and said Australia needed to improve, particularly its defence and support for teammates.
Preston said he would review footage and focus on defensive details before the final pool game.
He singled out leaders Isaah Yeo and James Tedesco for guidance, saying, "whenever they talk, we listen".
Preston knows the World Cup remains unfinished business and says there is more work ahead.