The wily campaigner ripped through the Volts line-up, taking seven for 105 on day two at the University Oval.
He also denied all-rounder Jimmy Neesham with a wonderfully clever spell of bowling which left the batsman bereft of ideas.
Wellington will resume on 107 for one hoping to stretch its 12-run lead into a total it can defend.
Earlier, it appeared the competition leaders would face a large first-innings deficit.
However, a flurry of wickets before the lunch break proved decisive.
Patel engineered the collapse. First he lured Anaru Kitchen into a drive and bowled him for 64. Michael Rippon got an inside edge to the man in close, while Mark Craig was trapped in front to complete Patel's 27th first-class five-wicket bag.
Otago went to lunch at 199 for seven and Patel had to work hard for the next wicket. He used all of his skill and smarts to get inside Neesham's head. The batsman had looked in good touch and was scoring freely.
But he stalled at 93 and it was Patel who built the road block. The 37-year-old came over the wicket to the hard-hitting left-hander and pinned him down.
The frustration was building after a couple of maidens. Then Patel beat the edge of the bat with a cracking delivery which spun from leg and missed off.
Neesham stayed in the spot, head down. His batting partner, Neil Wagner, wandered down the wicket to have a chat, but shortly afterwards Neesham tried to hit his way out of the corner he had found himself in and was caught at mid-off.
He smashed the bat on the ground in annoyance but that was some bowling from Patel. And some batting from Neesham, as well. He had looked fluent before Patel struck.
Wagner was out not long afterwards. having started off circumspectly before slugging his way to 40. The last pair of Michael Rae and Jacob Duffy teed off, whacking 31 from 20 to extend Otago's first innings lead to 95 runs.
Patel eventually bowled Rae to complete a terrific spell and his best return for Wellington.
He now has 299 wickets for the province.
On Saturday, Otago had one of its better days in first-class cricket this summer with spinners Rippon and Craig tearing through the Wellington line-up with four wickets apiece.
The Volts resumed on 80 for two at stumps without all-rounder Shaun Hicks, who was replaced in the morning by Rae as a concussion substitute upon medical advice. He was hit on the helmet while fielding in close on the opening day.
In the other games, Auckland needs another 168 runs with five wickets in hand to make Central Districts bat again at Eden Park Outer Oval.
In Whangarei, Canterbury is 141 for two in its second innings and trails Northern Districts by 75 runs.
