The opener's duck and delayed concussion were rare setbacks this week for SA, who dominated Victoria to win by an innings and 40 runs in the Shield opener at Junction Oval.
Nic Maddinson's first-innings Test failure in South Africa again highlighted the brittle Australian top order.
Weatherald was dropped from the Test side two months ago after the shock loss to Bangladesh in Darwin.
His domestic season started brightly enough last month with 92 in the one-day win over Tasmania.
But while fielding on day one of the Shield game, Weatherald slid into the Junction Oval boundary fence.
He then made a sixth-ball duck late on the first day and was subbed out at the start of day two because of delayed concussion symptoms.
Captain Ben Manenti and coach Ryan Harris said Weatherald had reported no issues before batting.
Manenti also strongly backed Weatherald to be a key contributor in their bid for a third-straight Shield title.
"He was pretty unlucky - he kept sliding and next thing you know, he clipped the fence," Manenti told AAP.
"But Weathers has been batting really well, he's been great to have back around the group.
"We know what a class player he is and also how hungry he is to try to get back to that Test level.
"For his sake and for our sake, if he's going well, he's going to get that opportunity and if he's doing well we're seeing him score a lot of runs for us."
Manenti and debutant Noah McFadyen scored their maiden first-class centuries as SA amassed 508, after Victoria opened the game with 244.
The home side ended day three on 7-175 and were bowled out before lunch on the final day for 224.
"We judge ourselves pretty harshly and hold ourselves to really high standards," Manenti said.
"We felt we missed the mark a little bit with the ball on day one ... but then we countered that and did really well (in Victoria's second innings).
"We were ruthless in our line and length and our plans in what we wanted to do. It's a great start."
Manenti (128) and McFadyen, who top-scored with 134 and took the final wicket of the game, piled the pain on SA with their lower-order knocks.
"I've thrown away a couple of bites at it, so it was nice ... and Noah batted awesome," the SA captain said.
A clear highlight for Victoria was debutant Harry Hoekstra, who took Weatherald's wicket. He finished with 6-103 and top-scored in the first innings with 45.
"Not ideal ... but there's a positive in what we found out of Harry Hoekstra - he gets the opportunity and shows what he can do, both with bat and ball," captain Peter Handscomb said.
"SA are back-to-back champions, they're the benchmark at the moment, so to come up against them, first round, is tough.
"But we know how close we are to it, to playing the way we want to play."
Fergus O'Neill top-scored in Victoria's second innings with 62, while Nathan McAndrew and Henry Thornton took three wickets apiece.
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