Manawatu's lead did not last long, as Ioane found Nareki with a long cross-field kick for the southerners' next try. Neither of their touchdowns were converted though and when Black slotted his second penalty, scores were still tied.
As halftime loomed, Turbos lock Jackson Hemopo, who fronted for the Highlanders during Super Rugby, latched onto a lineout throw and surged over for a try that took his team into the locker-room 20-13 ahead.
Manawatu had enjoyed overwhelming territorial (63%) and possession (62%) advantages, but Otago seemed intent on reversing that trend after the restart. Twelve minutes into the second half, fullback Vilimoni Koroi found some space and fired a long pass for Mitchell Scott to score out wide.
Scott set the groundwork for their next try, when he moved infield and held the ball up in a tackle, providing the platform for his forwards to rally around and eventually drive skipper Sam Anderson-Heather over in his 50th game for the province.
Replacement Fletcher Smith converted, something Ioane couldn't achieve with the previous three attempts, but the lead was again short-lived. Next time up the field, Manawatu halfback Jamie Booth was on hand to take an offload and dive over, with Black's conversion restoring the Turbo's edge.
But Nareki had his try double, when the home team stretched Manawatu's defence, and then a third, as he found space off a set move from a scrum and shrugged off defenders en route to the line.
Over the final 10 minutes, the green-and-whites threw everything at their rivals, with Laumape again threatening, but the Otago defence held firm for victory.
Otago 40 (Jonathan Ruru, Sam Anderson-Heather, Mitchell Scott & Jona Nareki 3 tries; Josh Ioane penalty, Fletcher Smith two conversions & penalty) Manawatu 30 (Ngani Laumape, Jamie Booth & Jackson Hempopo tries; Otere Black three conversions & two penalties, Jade Te Rure penalty)