Four reserve drivers in Russia GP practice

There will be four reserve drivers in action in Friday's first practice session in Sochi, as teams prepare for the Russian Grand Prix.

Lando Norris will continue his preparations for McLaren, with the junior driver replacing Stoffel Vandoorne next season, with a few practice sessions already under his belt this season.

"Lando will once again drive in FP1 in Russia," McLaren's sporting director Gil de Ferran revealed. "It will be a busy weekend for him, as he combines his F1 duties with his F2 championship campaign. Nevertheless, this will hopefully be another positive step in his development."

Antonio Giovinazzi will again be on Sauber duty in FP1, with the side still debating who will partner Kimi Raikkonen next season.

Marcus Ericsson's future is in huge doubt with Giovinazzi looking like the most likely candidate to replace the Swedish driver.

Artem Markelov will be on Renault duty, replacing the outgoing Carlos Sainz Jr. on Friday - Markelov won't have a chance at securing a Renault seat next year with Daniel Ricciardo linking up with the team, to drive alongside Nico Hulkenberg next season.

And Nicholas Latifi will be driving in place of Sergio Perez in his Force India car.

With Japan just a week after Russia, there is slight pressure on the drivers to perform well, with not much time to fix any mechanical/technical problems with the car.