South Otago relinquished control of the Crosby Morris Trophy with their second loss in as many weeks.
The holders were beaten by Upper Clutha by six wickets in Milton on Saturday.
South Otago skipper Dylan Bungard opted to bat, and openers Jeremy Gray and Shannon Young put up some tidy resistance.
Young showed his class with one of the shots of the day to get off the mark as he ploughed a drive through the cover region for four.
The opening partnership reached 27 before Young was dismissed attempting the same kind of drive off the bowling of Dan Snyman.
Snyman grabbed a second wicket in his next over with Gordon Edwards succumbing to the short-pitched attack, and Gray soon fell lbw to Marco Di Cesare.
William Casey and Brad Frost set about restoring the innings and forcing Upper Clutha to rotate their bowlers after a solid opening shift, but just as Frost looked to be finding the middle, he was bowled by Josh Eade.
Casey needed someone to bat with, and Bungard was batting positively until he fell to an lbw decision.
When Casey departed just before drinks, South Otago were on 97 for six.
Some fine strokesmanship from Quentin Gare was the only highlight of the lower order as South Otago were bowled out for 128 with 15 overs left in the innings.
Gare made early inroads with the ball when he dismissed Upper Clutha captain Blayne Wegener cheaply.
Opener Hardik Patel put in his customary effort with the bat, swatting boundaries to take the scoreboard pressure away from the visitors.
Gare grabbed another deserved wicket with Will Anderson holing out, and Gray claimed the important wicket of Patel to leave Upper Clutha 49 for three.
A decent partnership between Snyman and Sam Harper took Upper Clutha to 93 before Harper was caught behind, while a cameo from Di Cesare took the score over 100.
South Otago sniffed a chance, but Snyman and Josh Eade saw Upper Clutha home with plenty of overs spare.
By Francis Parker
