Marussia says Alexander Rossi has joined the Formula One team as its new reserve driver.
Rossi was in the same role with the Caterham team for two years, and also competed in the GP2 development series.
“He is a proven talent whom we have observed in GP2 and we have also been impressed by his performances during Friday morning free practice sessions over the past two seasons,” said Marussia team principal John Booth.
“The US is an exciting market for the sport and Alexander has a great deal of support there, so it is nice to develop new links to that audience,” he added.
“Alexander will be an integral part of the team, immersing himself in our engineering activity so that he is fully prepared should he ever be required to deputise for one of the race drivers.”
The Russian team has been competing in F1 since 2012 and has two points this season after ten races -- a ninth place achieved by Jules Bianchi at the Monaco Grand Prix. Marussia's other driver is Max Chilton.
Rossi, who said the move was "the next step" in his F1 career, joined the team on Thursday, ahead of the Hungarian Grand Prix on the Hungaroring.
"I'm delighted to be immersed into the team... with plans to drive in free practice one this season," Rossi said. “Marussia is in an exciting place right now and the progress at the team is clear for all to see."