LONDON, July 20 (Reuters) - Porsche's Pascal Wehrlein took a three-point lead in the electric Formula E championship on Saturday with his third win of the season and one round remaining.

The German ex-Formula One driver, who had been third before the start, will go into Sunday's final race at London's ExCel with Jaguar's New Zealanders Mitch Evans and Nick Cassidy his closest rivals.

Previous leader Cassidy, who started 17th and finished seventh, is now seven points behind after the 39-lap race.

The title hopes of DS Penske's Jean-Eric Vergne, Nissan's ( NSANF ) Oliver Rowland and Porsche's Antonio Felix da Costa, are over with all three failing to score.

Wehrlein passed pole sitter Evans, who also took a bonus point for fastest lap, mid-way through the race and held on despite a late safety car. Envision's Sebastien Buemi was third.

Cassidy finished with bent steering after banging wheels with the Andretti of last year's champion Jake Dennis.