Di Grassi takes maiden Formula E pole
Lucas di Grassi put aside an earlier practice crash to take his first ever Formula E pole position at Buenos Aires.
The French driver's front-row start banished a litany of errors from his team at the first two Formula E races as the Techeetah driver converted his Renault powertrain's pace with a time just 0.194s off di Grassi's.
"It is a great moment and not something I expected," said di Grassi afterwards.
"It is important after the first two races to get pole here, almost on home ground for me."
Championship leader Sebastien Buemi lost time in the first sector of his lap by locking his brakes.
The Swiss ultimately paid the price and slipped behind di Grassi and Vergne to start third.
The NextEV pair of Oliver Turvey and Nelson Piquet start fourth and fifth.
Both lost significant time on their superpole laps with major lock ups at Turns 7 and 1 respectively.
Nicolas Prost was the fastest qualifier who didn't make the superpole session and so starts sixth in his Renault e.dams entry.
The top 10 is filled out by Mitch Evans, Felix Rosenqvist, Jerome d'Ambrosio and Sam Bird.
Evans topped his qualifying group in his Jaguar I-Type 1, the time representing a major improvement for the team over its previous performances to secure its best starting position of seventh.
Evans' team-mate Adam Carroll starts from 15th position.
Last year's victor and practice pacesettter Bird had a self-confessed 'scrappy lap' due to his DS Virgin car struggling to achieve optimum grip levels, while team-mate Jose-Maria Lopez tagged the Turn 5 wall on his lap and caused a red flag.
Antonio Felix Da Costa's wretched day continued as he damaged the front right of his Andretti ATEC-02 before he had even started his qualifying lap and starts from 17th on the grid.