Adam Reynolds had just missed the chance to draw level with the Cowboys, but Souths coach Jason Demetriou backed the captain to nail his shot at redemption.
Unperturbed by failing to convert Alex Johnston's 76th-minute try from the sideline, the premiership-winning halfback slotted a penalty goal moments later.
He then marshalled the Rabbitohs forwards expertly before nailing the 20th field goal of his storied career to steal a last-gasp 31-30 win.
The frantic finish left many mouths agape but Demetriou, whose head coaching win record stands at 100 percent after two games in charge with Wayne Bennett on a COVID hold, wasn't surprised.
"As soon as that penalty was given, his hand was straight up. He wanted that footy in his hand and when he was doing that I was pretty confident he'd nail it," Demetriou said in Townsville.
Match Highlights: Cowboys v Rabbitohs
"Even the field goal set, you could see him pointing around, telling the boys to get to the field position that he wanted. He's a leader of the club for a reason, in big moments he wants the ball in his hands.
"I thought him and Cody [Walker] at crucial times, in terms of creating tries, was outstanding tonight as well."
Demetriou said five-eighth Walker, who was credited with two try assists and two line break assists, came up with some "special plays" on the left edge as Souths went tit-for-tat with North Queensland.
He paid tribute to the Cowboys, who he thought played their best game in at least a month, and predicted they would cause problems for other teams in the remaining six rounds.
Reynolds with the ball on a string
As for himself, Demetriou will return to his usual assistant duties with Bennett to emerge from his two-week isolation period in time for next Saturday's clash with fellow finals aspirants Manly.
Demetriou said he'd loved the taste of being a head coach as he prepares to succeed Bennett in the top job in 2022.
"I've been privileged to be able to do that. Fortunately the boys have responded well," he said.
"[I've got to] give a big rap to the other staff as well - Ben Hornby and Sam Burgess and John Sutton and Joe O'Callaghan [and] our high-performance staff have all done a good job pitching in.
"It's been a real team effort from the staff to cover Wayne's absence, but I'm excited to have Wayne back next week as well."