Will Hamilton starred for Valley with a six-wicket haul against Taieri, while Albion all-rounder Patrick Arnold picked up five scalps during the four-wicket win against CDK.
Green Island recorded a five-wicket win against University-Grange in the other encounter.
Taieri 132 lost to NEV 134/3
North East Valley right-arm seamer Will Hamilton snaffled six for 29 to lead his side to a comfortable seven-wicket win at Logan Park.
He tore through the Taieri top-order, accounting for the dangerous Ruben Clinton (25) and fellow opener Henry Olliver (27) to help rout the side for 132.
He also bowled Jack Kelly, who collected a hard-hit 30 before his departure.
Hamilton helped mop up the tail to ensure a comfortable chase, although No 11 Regan Flaws added 19.
Swans opener Thorn Parkes blasted 69 from 47 balls, and fellow opener Sebastian Lauderdale-Smith chipped in with 24 in an opening stand of 68.
Nikith Perera hit the winning runs in the 19th over.
Zac Cumming was the best of the Taieri bowlers. The Otago wrist spinner took two for 28.
CDK 99 loss to Albion 102/6
Albion all-rounder Patrick Arnold nabbed a five-wicket bag to help set up a four-wicket win against CDK at Tonga Park.
Otago opener Jamal Todd smashed 45 from 45 at the top of the CDK order. But he got virtually no support.
Mason Gain was the next leading scorer with 15, and Alfie Omelvena-Flame made 14 not out.
Arnold ripped through the top order, taking five for 23, and Eagles captain Lahiru Vimukthi claimed four for 32.
The chase had a few hiccups.
Todd took two for 22 and Alex Gordon grabbed two for 30.
But New Zealand under-19 representative Marco Alpe struck 37 from 37 balls and Ollie Ritchie whacked an undefeated 36 from 26 balls to help seal the win.
University-Grange 155 lost to Green Island 159/5
Angus Henry dragged University-Grange through to 155 with an undefeated knock of 68 at Sunnyvale.
But the aggressive Yuvraj Khara thumped 60 not out from 35 balls to help his side post a five-wicket win.
Khara clubbed four sixes and five fours with some meaty strikes.
Joel Pannell did his best to keep his side in the contest. He took four for 50, removing Green Island’s talented top four.
The home side had slumped to 58 for four before Khara started bashing it.
Earlier, Henry had batted nicely.
He kept his wicket intact for more than an hour and a half. But Lochie Mavor (four for 51), Jacob Cumming (two for 41) and Elliot Santner (two for 13) kept chipping away at the batting order.
