By alley - Apr 9, 2015, 8:31 AM ET

F1: Sainz thinks Toro Rosso can match Williams

Toro Rosso driver Carlos Sainz Jr. says his Formula 1 car is "at the level of Williams" and that it could challenge the team if Renault makes top-speed gains.

The Spaniard has made a strong start to his F1 career, finishing in the points in Australia and Malaysia to help the team sit fifth in the constructors' championship, in line with its pre-season target. Although that currently puts Toro Rosso ahead of Red Bull, Sainz reckons the senior squad's development program means it will "end up being up there." But he thinks the STR10 is strong enough to challenge Williams – last year's third-placed team – subject to Renault's progress.

"I see Williams like they have a very strong baseline from last year, and that they're using this strong baseline to perform this year," Sainz said. "I really feel like we have a great car on the corners; we are at the level of Williams in terms of downforce and corner speeds. We just need the top speed that hopefully through the year comes, and we can start fighting with them."

Both Red Bull outfits have been hamstrung by Renault's power unit and while major driveability gains were made in Malaysia, Sainz estimates the package is still "seven or eight" kilometres per hour down on the Mercedes and Ferrari-powered teams in a straight line.

"[It] is making racing a bit tough, the lack of power," Sainz said. "For me, the main concern in Melbourne was the driveability and they absolutely made it perfect for Malaysia.

"At least the driver can focus solely on his racing and his setup because driveability was not an issue, it's a huge step forward."

LEADING CONSTRUCTORS' STANDINGS: