Daring Riverside captain Tom Garwood called it first overnight and his bold Blues bowlers delivered it the next morning at Windsor Park.
"It was one of those pitches that once you get on a bit of a roll, it takes a bit of toll especially to the tailenders," a proud Garwood said.
"We know that because we did exactly the same and lost five for nearly none. So there was belief there this morning that we could definitely do it.
"I felt the guys rocked up with the right attitude and bowled quite well, actually."
In a tense first 70 balls to Sunday's resumption of play, Riverside clinched a miraculous two-run triumph.
Miraculous in the sense of South Launceston, who had needed 17 more to win, going all but four or nothing.
In pursuit of running down 169, it took 25 balls before that sequence was broken and then it was singles only.
They crept a bit more when Sam Lockett denied Sean Harris a century, only capable of adding his 16th boundary and was dismissed eight short of the win for 95.
But it was Blues coach Lyndon Stubbs that took care of business and cleaned up the Knights' nervous tail.
The seasoned spearhead removed the last three victims, catching out Anders Bulow (9) and cleaning up Jackson Young (2) and Josh Freestone (1).
The final four wickets were gone for just five runs.
"Lyndon's experience with his line and length is really good," Garwood said.
"Obviously, Sean was a big wicket and we knew Lockett loves to take a big wicket, so that's why we bowled with him straight away."
There was a late twist in the battle to come.
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Riverside batted a second time and were outed for 184, as Knights spinner Jeremy Jackson claimed 4-38.
Garwood had accumulated 85 off 144 balls, which in the context of the game may have staved off an outright.
South had the Blues field spread early on in pursuit of the unlikely extra points, but settled on 6-125 off 25 overs.
Launceston delivered on an expected win over Mowbray at Invermay Park.
The Lions had 294 to defend after declaring late on Saturday and having the hosts 1-15 following Sam Canny's first-ball duck.
"The boys played really well, I reckon," Launceston captain Alastair Taylor said.
"Obviously, Ethan was the standout yesterday with the bat, and he got involved in a really nice partnership with James Curran. They got us to a really competitive total.
"The side toiled pretty hard on a pretty nice batting wicket to get the 10 wickets."
Mowbray to its credit was prepared to take the game up to Launceston.
Three sizeable partnerships between 49 and 64 tested the patience of the hungry Lions' attack.
But the visitors could taste blood and pulled off a series of back-to-back breakthroughs with 2-1 early on, 2-4 in the middle-order and 5-35 at the death.
Luke Scott with 55 and Jonathon Jones with 48 were tempered by Zac Oldenhof with 4-28 late in the game and Jakeb Morris 3-26 earlier.
"Credit to Zac Oldenhof, who bowled really well and Jakeb Morris as well," Taylor said. "Those boys put the ball in the right areas enough."
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