When it comes to sportscar racing, former Toro Rosso driver Brendon Hartley has been long associated with Porsche and was a key part of the works team's 2017 victory at the 24 Hours of Le Mans.

So it was something of a surprise when the German manufacturer decided not to include the New Zealander in its driver line-up for its maiden season in the ABB FIA Formula E championship.

Hartley explained that Porsche had decided it needed to have a more experienced line-up in place to help it hit the ground running in its first campaign in the all-electric series.

With that in mind, Porsche signed Andre Lotterer from the title-winning Techeetah team to partner Neel Jani, who will make his series debut in Formula E in the season opener in Diriyah on Friday.

"I would have loved to have taken the seat but there was never a promise," Hartley told Autosport magazine this week. "There was always the chance - even late on into the project, I was doing a good job in testing

"But I think for them to take two rookies it would have been a high risk," he acknowledged. "I always understood Neel was already signed, so it made sense that they took another driver with experience - a known quantity."

"I always knew that that could have been on the cards," he said, insisting that he harboured no bad feelings over the outcome.

Hartley will still be on the grid for the doubleheader even after securing a spot with the GEOX Dragon Racing team instead alongside Nico Muller.

"There is no animosity from my side they were incredibly fair to actually allow me to go and take on an opportunity in another race team.

"I have to thank them for that and now I am really looking forward to this new project with Dragon."

The 30-year-old from Palmerston North predicted that Porsche would be competitive straight out of the gate, and said that there was bound to be a "friendly rivalry" between the works team and himself.

"I'm sure I'm still welcome to go down and have a coffee and say 'g'day'," he said.

However the switch does mean that he will give up his role as a Porsche factory driver, as there's "obviously a conflict if we're competing against each other".

"I'd like to think I'll always be somewhat a part of the family, but contractually I won't be involved next year."

With Porsche no longer taking part in the World Endurance Championship, Hartley is now putting his sportscar experience to good use by linking up with the Toyota LMP1 team in place of Fernando Alonso. That makes him a WEC team mate with Formula E rival Sebastian Buemi.

The schedules for the two series clash in March, with Hartley opting to take part in the Sebring 12 hours event over Formula E's visit to China the same weekend.

"Contractually for me the WEC takes priority," he explained. "It's not ideal, but I'm happy to still have the opportunity to take part in both championships."

Gallery: The beautiful wives and girlfriends of F1 drivers

Keep up to date with all the F1 news via Facebook and Twitter