SMP Racing driver Matevos Isaakyan will complete the Formula 2 season for the Sauber Junior Team in place of injured Alfa Romeo Formula 1 junior Juan Manuel Correa.
Correa was involved in the crash that claimed the life of Anthoine Hubert at Spa in F2 last month, and continues to be listed as critical but stable in intensive care in London with leg injuries and breathing complications.
Russian driver Isaakyan finished second in the Formula V8 3.5 championship in 2017, before contesting four World Endurance Championship events for SMP in its BR Engineering BR1 in the 2018/19 season. SMP has pulled out of the WEC for 2019-'20.
The 21-year-old is familiar with the F1 support-series paddock, as he raced for Koiranen GP during the 2015-16 GP3 Series season.
"I'm excited to drive in the F2 championship, especially in my home grand prix," said Isaakyan.
"This is quite an unexpected development in my season but I'm very thankful for this opportunity and happy to join the team.
"It won't be an easy job as I'll be jumping straight in the car for Sochi practice.
"The biggest thing will be understanding the tyres - that will be the main focus for me as it was when I did GP3.
"But I don't think it will be an impossible task to try and get into the top 10 and score some points."
Antonin Charouz, owner of the Charouz Racing System team which runs the Sauber Junior Team entry, added: "We're pleased to welcome Matevos to the team for his home F2 race in Russia and also the final round in Abu Dhabi.
"He has a proven pedigree in single-seater racing and we're excited to see him join the F2 grid.
"It's always a difficult situation when one driver stands in for another but we're ready to do our best and to finish the season positively."
Isaakyan joins Ferrari F1 junior Callum Ilott in the team's line-up.
Correa developed Acute Respiratory Distress Syndrome after the accident, meaning his lungs filled with fluid and he required a machine to allow him to breathe.
A family statement released on September 17 said: "Although his lungs have gradually recovered, his respiratory functions continue to be assisted by ECMO and a breathing ventilator.
"Juan Manuel's leg injuries remain an important concern and will undergo immediate surgery once his lungs are strong enough to withstand the procedure."