Red Bull junior squad Toro Rosso has its sights set on becoming one of Formula 1’s top five teams in 2015, despite starting a season with two rookie drivers for the first time in its history.

Second-generation racers Max Verstappen and Carlos Sainz Jr have been lifted into the squad this year from the European Formula 3 and Formula Renault 3.5 ranks respectively.

Seventeen-year-old Verstappen has garnered much attention since being awarded the drive late last year, with his tender age leading the FIA to review its Super License system for 2016 onwards.

Verstappen’s sudden promotion had appeared to dash Sainz’s hopes of an F1 slot, before Red Bull star Sebastian Vettel’s defection to Ferrari triggered a chain reaction down the grid.

Toro Rosso’s European winter testing schedule ended with a positive final hit-out in Barcelona, which saw the team roll out a significantly upgraded car.

Although buoyed by the testing program, Sainz Jr says that the all-rookie line-up will add a further degree of difficulty at the notoriously tumultuous season opener.

“It will be very challenging because obviously we don’t have any data here from past years with this car,” Sainz told Speedcafe.com at Albert Park.

“We will have to look at each other, try to take the good bits and go forward.

“It’s not going to make things easy, but it will be challenging and interesting.

“It’s a new track for both and it’s a very challenging track for a rookie, from what I saw on the track walk and in the simulator, especially if it rains.

“You can see a lot of races in the past with rain, on extremes or inters, changeable track conditions.

“If it suddenly starts raining the experienced drivers have all the references from previous years, but we are completely new.”

Although the team appears a strong chance of sneaking into the points on Sunday, Sainz says its prospects will be hard to gauge prior to the race itself.

“You never know because you can come here and suddenly McLaren are up there and finish the race, then you have the top five teams in the points,” he said.

“Our target is obviously to beat one of those top teams and finish fifth in the championship.

“I think we have the car to do that after what we saw in testing with the new aero package (debuted at the final test).

“The car is behaving very well and everyone is happy, (but) we need to do everything perfect.”

The attention on Verstappen has largely shielded Sainz from the media spotlight ahead of his first grand prix.

Within the team, however, the reigning Formula Renault 3.5 champion insists that expectations on the drivers are the same.

“There has been a lot of talk about my team-mate in the press but in the team we are equal, so we have the same amount of pressure and the same requirements,” he said.

“They trust both Max and myself in our abilities and in the end the pressure I get is from myself and the team.

“At the end I am calm about it. I know what I have to do and I know what the team wants me to do and that’s the most important thing.”

Sainz has his World Rally Championship winning father by his side at Albert Park, 12 years on from the now 52-year-old’s final competitive appearance on Australian soil.