Although the Faenza-based team had some difficulties with reliability of the new Renault engine at Barcelona this week, both Carlos Sainz and Daniil Kvyat were encouraged by the performance of the chassis itself.

And, amid faith that Renault's engine problems can be sorted, team boss Franz Tost is upbeat that it can do well in the group of the cars that are expected to be behind Mercedes, Red Bull and Ferrari.

"We don't know how much fuel all the other teams are running, but I am optimistic that Toro Rosso will be in the front part of this midfield," said Tost.

"This week about our car: it looks good, it looks fast, and the drivers are doing a good job. If we get everything under control from the technical side, I am convinced we can achieve our goal."

Toro Rosso technical director James Key believes that the midfield contest would be especially close this year, with a number of teams having shown strongly in the first test.

"I think Haas looks quite reasonable, they are looking in reasonable shape," said Key, responding to a question about who he believed would be the team's strongest rivals.

"We have to see how that develops next week and into Melbourne. But they have done a good job,"

"Renault. It could be tight with them, we have to see. They look on balance more competitive than they did last year. Williams is difficult to tell at the moment and I think it is difficult to tell with Force India as well."

When asked whether it was significant he had not mentioned McLaren nor Sauber, Key said: "No disrespect to them but you asked me to pinpoint who I thought was good…. I don't think we can tell from either of those two teams at this stage.

"I guess McLaren like us have had the dramas this week. Clearly they haven't put a full programme at this stage so I don't think it is easy to comment, but I am sure everyone is very fast…."