In a Uruguayan resort famed for its casinos, Vergne was certainly the recipient of good luck, as the Frenchman was elevated from fifth to pole after all four drivers who qualified in front of him were demoted by stewards – a position he held for the entire race.
But fortune favours the brave and the 27-year-old showed his considerable skill behind the wheel of his Techeetah car, as gave a textbook display of defensive driving to hold off a fiery Di Grassi.
Panasonic Jaguar Racing’s Mitch Evans was the driver of the day as he produced a stunning performance through the field after a qualifying disaster – the precocious 23-year-old flew through his laps to rise from 16th to finish fourth.
As the gaps between the manufacturers continues to tighten, five different teams qualified into a Super Pole showdown which became a disaster for nearly all involved. Despite a poor lap nearly two seconds off the pace, Vergne benefitted from Mitch Evans, Oliver Turvey, Lucas di Grassi and Alex Lynn all being disqualified - the latter three for hitting the same bollard on the last chicane.
Evans, who looked to be in good position to start pole, was pushed all the way to the back of the grid after his car was found to be non-compliant with FIA stewards.
The race was barely underway before its first incident, with Nick Heidfeld losing some bodywork at turn one as the grid became a concertina and he clipped an Andretti car, ending his race and bringing out the Qualcomm safety car.
Sebastien Buemi has been one of the most consistent drivers with three podiums in a row and had also won the last two E-Prix in Punta, but his love affair with the beachside circuit came to an end on lap 11, having broken a rear wheel whilst perusing Daniel Abt. The Swiss did not finish the race.
Vergne had maintained his lead despite his team radio going down and during the pit stop the Techeetah team were quick enough to maintain the status quo of Vergne and di Grassi in first and second.
And just moments after, di Grassi’s race was nearly over as he made an aggressive overtake on the race leader who held his line and nearly forced the Brazilian to spin out into the wall.
Race winner in Mexico, Abt had begun the previous race in sixth only to win and he could sense a similar result when he jumped up into third thanks to a rapid Audi Sport ABT Schaeffler pit stop. But it turned into a disaster as the German’s seatbelt was left unfastened so he had to return to the pits and dropped to 15th.
Britain’s Sam Bird also made the most of the pit stop to come out in front of his DS Virgin Racing teammate Alex Lynn to move into the podium places behind Di Grassi and Vergne who were having their own private battle at the front of the grid.
But it was Evans was producing the overtakes – one an unbelievable inside manoeuvre on Lynn at one of the fastest corners in Formula E to climb up to fourth.
At the front, Di Grassi seemed to be setting up overtakes on every turn but Vergne pulled off some superb defensive moves time and time again. However, this battle allowed Bird to close the gap and compete for the lead in the last few laps.
In the final lap di Grassi continued to push Vergne all the way - even clipping the rear of his car on the final turn - but he held on for the win, and admitted afterwards that he needed a “glass of vodka” after one of the most thrilling battles of the season.
Vergne leads the ABB FIA Drivers’ Championship by 30 points ahead of Felix Rosenqvist, who finished the race in fifth, and Britain’s Bird, who ended third and has now closed the gap to Rosenqvist to just three points.
The ABB FIA Formula E season now heads to Europe, with the Rome E-Prix on Saturday 14th April.