Mercedes and Ferrari "too fast" for Red Bull at Sochi

The two Red Bulls ended second practice in Russia in fifth and sixth places, with Max Verstappen ending up 1.420 seconds off the pace established by Ferrari's Sebastian Vettel at the head of the pack.

Ricciardo was a further three tenths slower than his teammate, ending up in the same position he finished Friday morning's opening session.

The Australian admitted that Red Bull's realistic target is to be "next best" behind the top two teams, with the Milton Keynes outfit struggling with both power and a lack of downforce compared to its rivals while it waits for a major update package to be introduced for the next round in Spain.

"In terms of us here this weekend, we know this is what we have got, so we are trying to do what we can with the current car and package," said Ricciardo.

"But we are not expecting anything too much this weekend. We will try to do what we can, get the job done and then hopefully fight for a bit more in a few weeks.

"We have to try to target the top five. When I say that – it is behind Ferrari and Mercedes. To try to be the next best after that is the realistic target for now.

"We can improve, but as far as positions go, fifth and sixth as a team is the best we can achieve so far. Ferrari and Mercedes are too fast."

Fuel pressure issue ends Verstappen's day

Verstappen's day came to a premature halt as he stopped on track with 20 minutes remaining of second practice, reporting he was "out of power".

The Dutchman revealed the problem was fuel pressure-related, while admitting that Sochi is not a track that plays to Red Bull's strengths.

"The problem we think is the fuel pressure," said Verstappen of his stoppage. "It is a bit of a shame of course, we couldn’t really do a long run.

"We need to look at what we can improve tomorrow, this track anyway is not our favourite so we just try to make the best out of it.

"We are quite a bit down on power, especially here, when you already don’t have the downforce you want. Then the corners and the straights together, that makes it just that bit harder."

Additional reporting by Jonathan Noble