The 17-year-old from Vancouver spent exactly two hours on court in a tight duel with his teenaged rival, who he beat for his first major title in the Traralgon junior event 160 kilometres from Melbourne only a week ago.
Peliwo fired three aces and 21 winners while committing 27 unforced errors.
"Luke played a great match, came out on top and played the better match," said Peliwo. "I played good tennis overall, but I didn't really do anything extraordinary.
"I wasn't returning quite as well as I'd like to, and a couple of bad games on my serve cost me. I wasn't able to break enough, and that's basically it, a couple of bad points."
Showcased on the Australian Open's main court — Rod Laver Arena — Peliwo went down a break in the second game of the match and was never able to close the gap on his rival, as Saville converted on his first set point after 32 minutes.
But Peliwo retaliated by winning the second set with a break of the Australian in the second game.
Peliwo managed a 3-0 lead before his opponent clawed back the break for 2-3 on a double-fault. He broke in the last game of the set to level.
Saville took a 1-0 lead on a break in the opening game of the third and finished with an untouchable service winner.
Peliwo, who turns 18 on Monday, lost his first match of the 2012 season after 11 consecutive victories. He's ranked No. 7 in the ITF junior rankings.
He said that even with the end of his winning streak, his season is off to a remarkable start.
"It's definitely my best streak of my career, besides the loss here I'm very satisfied with my performance."
Peliwo's the first Canadian since Vancouver's Philip Bester and Peter Polansky of Thornhill, Ont., in 2006 to reach a junior Grand Slam singles final.
"Thanks to the team back home in Canada, they did a lot of work and it paid off for the most part," said Peliwo. "I had so much support from back home form those who support Canadian tennis."
Peliwo trains a the National Tennis Centre in Montreal.