A strong third term allowed the Power to hold a six-goal break at the last change before winning 21.14 (140) to 12.11 (83).
Draftee Krakouer banked the first two goals of the game and finished with three, and former Richmond rover Rodan proved a bundle of energy to boot four of his own, a tally matched by forward pocket Brett Ebert.
Port's speed was a headache for new Saints coach Ross Lyon, with Danyle Pearce also nabbing two goals and Peter Burgoyne eye-catching when rotated off the bench.
Goal-poacher Stephen Milne fired through four goals for the Saints.
Former Crow Matthew Clarke had a nondescript return to his former home ground, shaded in the ruck by Port's Dean Brogan.
Coach Mark Williams enthused over the contributions of his younger players.
"It was pretty exciting to see what some of them could do and I'm sure our supporters would've enjoyed seeing it," he said.
Williams said ex-Tiger Rodan was playing like a man who had something to prove.
"If you're picked up at 88 in the draft and you know there's a lot of guys coming back through the squad after injury, then there's a fair chance you're going to find it hard to get in," he said.
"He's playing like someone who's wanting to prove something and he's growing in confidence, he's earned the respect of a lot of the players with the work he's done."
PORT ADELAIDE: 4.4, 10.9, 14.12, 21.14 (140)
ST KILDA: 3.3, 7.4, 9.8, 12.11 (83)
GOALS – Port Adelaide: Rodan 4, Ebert 4, Krakouer 3, Willits 3, Pearce 2, Cockshell 2, Motlop, Boak, Gray. St Kilda: Milne 4, Blake 2, Ball 2, Montagna, Brooks, Rix, Gram.
BEST – Port Adelaide: Rodan, Salopek, Thomson, Lonie, Brogan, Willits, Ebert. St Kilda: Dal Santo, Harvey, Thompson, Goddard, Jones, Milne.
INJURIES - Cassisi (corked thigh).
UMPIRES - James, Sully, Nicholls, Fila.
CROWD - 4424 at AAMI Stadium.
