Lewis Hamilton and Mercedes hold the early advantage after setting the fastest time of Friday practice at the Russian Grand Prix.
Though it was Sebastian Vettel who led the morning session for Ferrari at Sochi, the championship leader and his Brackley-based squad, who are undefeated in all four previous races at the Olympic Park, pulled ahead in the afternoon.
Hamilton’s best time of 1m33.385s came on his third flying lap while using the Hypersoft tyre during the traditional lower fuel runs in FP2 and gave him a two-tenths advantage over teammate and 2017 winner in Russia, Valtteri Bottas.
Interestingly, it would be Red Bull who got closer to the Silver Arrows with Max Verstappen and Daniel Ricciardo both four-tenths back in third and fourth respectively.
Vettel would end Friday over half a second behind Hamilton in fifth as optimising the performance of the pink-striped compound appeared their biggest problem, indeed teammate Kimi Raikkonen would be over a second off the pace in sixth.
The only positive for the Scuderia is the looming engine penalties for Red Bull, which will drop both their drivers to the back of the grid after qualifying.
More worryingly for Ricciardo, he lost out on a good portion of the morning session due to a smoky problem at the back of his car with mechanics still watching the exhaust system in the second practice too.
Surprisingly for Sochi, tyre degradation was one of the main topics of the day as drivers struggled to achieve a prolonged stint with the Hypersoft compound.
Maintaining rear grip was the main issue with so many traction zones, particularly in the final sector, and even saw Vettel spin at Turn 13 during his race simulation.
A one-stop race does still appear the most likely, however, with the Ultrasoft and Soft tyre proving durable enough and, unlike Singapore, the performance gap between the Hyper and Ultra may be small enough to allow the top teams to use the purple-striped compound in Q2.
Entering the midfield where Force India led the way once again, as Sergio Perez and Esteban Ocon moved up to seventh and ninth in the afternoon.
Pierre Gasly hinted at the potential of the upgraded Honda engine being used this weekend in eighth for Toro Rosso, although he along with both Red Bulls, teammate Brendon Hartley and Fernando Alonso will all take grid penalties as a result.
On the week when it was confirmed he would be dropped by Sauber, Marcus Ericsson impressed by beating Charles Leclerc and finishing 10th, despite missing the first session as his replacement Antonio Giovinazzi drove in the morning.
Haas had a busier Friday than most after an overnight garage fire saw two sets of tyres destroyed and then the American team confirmed they would be retaining Kevin Magnussen and Romain Grosjean for a third straight year in 2019.
The performance on track was a little muted though, with K-Mag only 11th fastest albeit six-tenths clear of his French teammate in 15th.
Renault were also further down than expected as Carlos Sainz sat 12th and Nico Hulkenberg 14th although the battle was very close with just four tenths covering P7 to P14.
Bringing up the grid were the two McLaren’s and two Williams’ once again and the pace of Alonso was the only thing keeping him in touch with the midfield pack in 17th.
Sergey Sirotkin also has the edge on teammate Lance Stroll at his home race after the Canadian flat-spotted a set of tyres in FP1 causing him to lose half the session, putting him at a disadvantage to his Russian partner in the afternoon.
Full results from the second session can be seen below: