Toro Rosso's Max Verstappen follows Mercedes' Lewis Hamilton at the Hungaroring

Toro Rosso boss Franz Tost believes the team’s ambitious target of fifth place in the Constructors’ Championship is still achievable on the back of their best race for seven years at the Hungarian GP.

The 12 points Max Verstappen earned for fourth place in the unpredictable Budapest race represented the Red Bull junior team’s best result since their original protégé Sebastian Vettel also finished just off the podium in the 2008 Brazilian GP.

The finish moved Toro Rosso ahead of Sauber and onto the heels of Lotus and Force India in the fight for fifth in the championship.

With the highly-regarded James Key leading their technical department, the STR10 chassis has received plaudits since the start of the season, but only McLaren have endured more race retirements than Renault-powered Toro Rosso so far in 2015.

Tost acknowledges the team’s finishing record "isn't as good as it should be" but is hopeful they can kick on from the unexpectedly strong result in Hungary after the summer break.

"At the beginning of the year I thought we might be in a position to challenge for a top five position in the Constructors' Championship, having seen the figures from the wind tunnel and also the results of testing," he told Toro Rosso's website.

"And now I still tend to think we can do it, especially after our strong result in Budapest, as there are now only eight points separating us from the team that is P5."

The fight for fifth in F1 2015 5) Force India - 39 points

6) Lotus - 35 points

7) Toro Rosso - 31 points

8) Sauber - 22 points

9) McLaren - 17 points

Toro Rosso’s nine race retirements across their two cars in the opening 10 races have largely been attributed to the team’s Renault power unit, but Tost also admits "it's true that there have been mistakes on our side".

The Austrian reckons those reliability problems have held back a car which he says even rivals the dominant Mercedes W06 in fast corners.

"It's true, the aerodynamics is working very well and in some of the high-speed corners, it has been proved that the car is almost as good and sometimes even equal to the Mercedes," he claimed.

"During these first ten races we have unfortunately left quite a few points behind due to reliability issues. If it wasn't for this, we would definitely be further up in the Constructors' Championship, but we continue to work hard with our partners to improve this and come back stronger in the second half of the season."

The famously demanding team chief also had words of praise for the team’s all-rookie driver pairing of Verstappen and Carlos Sainz following the eye-catching starts the youngsters have made to their F1 careers.

Carlos Sainz and Max Verstappen have impressed so far in F1

"Both of our drivers have done a fantastic job and that is partly because of their commitment to Formula 1," Tost added. "They have a really positive attitude and Formula 1 is their life, which is clear from the fact they are in constant contact with their engineers, they spend a lot of time working on their physical condition.

"They are always asking questions and they have a strong work ethic. Formula 1 is their passion and that's the best route to success. I would say they are one of the most competitive pairings we have seen at Toro Rosso. Their learning curve is very steep."