The Renault F1 Team has announced that Sergey Sirotkin has been named as the team's official reserve driver for 2019.
After a single season with Williams in 2018, Sirotkin was forced off the F1 grid at the end of last year when the Grove team signed up Robert Kubica.
The 23-year-old Russian viewed F1 as unfinished business however and vowed to retain an active link with a team.
Sirotkin, who will dovetail his F1 commitments with a WEC programme with SMP, is well acquainted with Renault, having previously enjoyed a development role with the French outfit.
"I am very pleased to rejoin my friends at Renault F1 Team and return to Formula 1," he said.
"We are well acquainted with the team, I spent the whole of 2017 in their factory and in the garage.
"It will be interesting to learn how far Renault has advanced in the development of the car over the past year; last season we were rivals and I could not see the work from the inside.
"I am pleased to join the team as Third & Reserve Driver and work alongside Nico Hülkenberg and Daniel Ricciardo."
In addition to Sirotkin's hiring, Renault also announced the Campos F2 charger Jack Aitken, who graduated from the Renault Sport Academy in 2019 after a three-year tenure, will be handed testing duties with the F1 team.
Finally, Renault F1's junior line-up is completed by development driver Guanyu Zhou.
"In Sergey’s return, we have a driver who has experienced a full season racing in Formula 1 and that knowledge will be beneficial to developing our package," said Renault Sport racing managing director Cyril Abiteboul.
"Jack has also impressed us when testing our Formula 1 machinery, while Guanyu will complement the experienced team.
"All of them have an important role to play this season and we look forward seeing them all in action."