GP2 veterans Stefano Coletti and Sergio Canamasas will race for Campos and Trident in this weekend's Formula 2 season-opener in Bahrain, completing the championship's 20-car field.
Coletti competed full-time in GP2 between 2011 and 2014, taking seven victories, and finished a high of fifth in the 2013 standings while competing for Rapax, having led the championship mid-season before slipping down the order.
Coletti moved into IndyCar in 2015 but was unable to secure his seat and instead moved to the European Le Mans Series, but will now return to Formula 1's rebranded feeder series this weekend.
Campos tested Roberto Merhi and Raoul Hyman pre-season but Coletti will now link up with Ralph Boschung for the upcoming Sakhir event.
"I am glad with the deal that will see me drive for Campos Racing at FIA Formula 2 Championship’s season opener event in Bahrain," said Coletti. "I am looking forward to driving my car."
Canamasas, meanwhile, completed pre-season testing with Trident and will line up on the grid this weekend.
The Spaniard had started 90 races in the category, four more than fellow veteran Coletti, with two podiums, both achieved in Monaco.