The 27-year old Frenchman was the 2020 FIA World Touring Car champion and followed that up with a second title a year later, successfully defending his crown.
Ehrlacher has racing in the family, as the nephew of BTCC champion, touring car royalty and four time FIA WTCR champion himself, Yvan Muller.
The jump into GEN3 will be Ehrlacher's first foray into single seater machinery as well as his first outing in an electric race car, but the Frenchman has had experience with the team having completed sim testing duties with DS PENSKE.
"I am thrilled to get the opportunity to drive the new Formula E GEN3 race car," he says. "It’s a championship which is growing every day, and has a different approach compared with other racing series, and that is why this is so interesting.
"I am very excited for the session in Rome which is one of the most amazing venues on the Season 9 calendar."
Rookie Free Practice
Teams can field someone who's sampled Formula E machinery before, but they must not be drivers included on the Season 9 Entry List, and they must not have competed in a Formula E race in their career before. The idea is to give the best young talent a pathway to race at the very top of the motorsport ladder with a taste of Formula E and the opportunity to impress prospective teams in the world's leading electric race series.
READ MORE: Rookies set for Rome outing
The choices the teams have put forward to Formula E and the FIA will be revealed in the lead up to Rome.
Felipe Drugovich has already been confirmed at Maserati MSG Racing. The young Brazilian, who topped the timesheets during the Berlin Rookie Test earlier this year, will now get a second chance to impress during Rome’s Rookie Free Practice session. The opportunity, which is exclusively for rookie drivers, will see some of motorsport’s brightest talents navigate the iconic Italian street circuit and find their feet in the electric machinery.
Avalanche Andretti, meanwhile, have confirmed that Zane Maloney will once again get behind the wheel of their GEN3 car.
NEOM McLaren confirmed Charlie Eastwood for their seat in Rome while Mahindra Racing picked Jehan Daruvala to return in their car.
Yifei Ye will drive for TAG Heuer Porsche.