"There were some good parts to the performance and to get the result today, I was just really pleased for the manner in which they did it," said Kearney.
"Roger, the halves, and the dummy-half and the spine had really strong games for us.
"The boys have worked hard through the pre-season and we've made a couple of adjustments to our game style so our focus was just on executing that.
"It wasn't about this being the 10th time we're here or anything like that. It was just about executing our roles out there and I thought the guys did that pretty well."
New recruits Blake Green, Adam Blair, Tohu Harris Peta Hiku and Leivaha Pulu all performed strongly, while back-up hooker Sam Cook made his NRL debut after replacing Luke late in the match.
Green's organising presence allowed Johnson to rediscover his best form and showcase his unrivalled running ability, with the Kiwis test No7 ripping Souths to shreds in the first half.
A trimmed-down Luke produced his best performance in Warriors colours with some sniping runs out of dummy-half and a timely grubber earning a repeat set late in the first half.
First-half tries to Isaiah Papali'i, Sam Lisone, and a double to wing David Fusitu'a saw them enjoy a 20-10 halftime lead after the Rabbitohs scored twice through five-eighth Cody Walker and right wing Richard Kennar.
The Warriors continued their momentum early in the second-half with Tuivasa-Sheck playing a hand in tries to left wing Ken Maumalo and centre Solomone Kata to give them a 20 point advantage before Kennar scored going into the last quarter.
The Rabbitohs managed to stem the tide but forced their hand as they looked to play catch-up but they found reward late with Walker crossing for his second try in the dying stages before halfback Adam Reynolds booted the conversion to give him 1000 NRL points.
"That will give (the team) a lot of confidence," said Tuivasa-Sheck.
"It just gives us a bit of confidence and belief that we can stay in games and finish it off."
The Rabbbitohs looked rusty but dominated early on with a 7-1 first-half penalty count restricting the Warriors to just 30 per cent possession and keeping them down on their own line.
However, try-saving tackles from Tuivasa-Sheck and Pulu at either end of the first half prevented tries while a forward pass ruling saw Kennar denied on his first attempt.
The Warriors fly home to Auckland on Sunday and will look to continue their momentum and achieve back-to-back wins to start the season for the first time since 2009, when they host the Gold Coast Titans in their first home game at Mt Smart Stadium next Saturday.
Warriors 32 (David Fusitua 2, Isaiah Papali'i, Sam Lisone, Ken Maumalo, Solomone Kata tries; Shaun Johnson 4 cons)
Rabbitohs 20 (Cody Walker 2, Richard Kennar 2 tries; Adam Reynolds 2 cons)
