Sainz still not satisfied due to "underlying balance issues"

Carlos Sainz Jr. set the fastest time on Wednesday's day of testing in Barcelona, but the McLaren man isn't completely satisfied with its MCL34 - saying there are "underlying balance issues".

Sainz recorded a 1:17.144 in the morning session of Day Six of testing, and nobody could trump that or get anywhere near his time.

However, the Spaniard was not fully pleased as he headed back to the pitlane in Barcelona. He admitted there has been a gradual improvement in its car but there is still some real work to do before the first race of the season in Australia.

"There are still big areas of improvement needed, definitely," Sainz admitted. "The important stuff to come out of testing is that every time I go out on track, I think the car has been progressing.

"The car balance has gotten better over the last few days and that is allowing us to extract a bit more from it. So we're working well and understanding the underlying balance issues and correcting them little by little.

"But, still, there's a long season ahead and plenty of areas where we need to keep working. We're still not where we want to be. We need to keep working hard. Like, I mean, a 17.1 around Barcelona is fast but teams like Red Bull and Ferrari can go much faster than that.

"Pretty much everything has been improved (over testing). Like I said, (there are) still underlying balance issues that we're working on that we can't get rid of until we bring an upgrade to the car, but that is what is Formula 1 is about. We try to improve and in the next races, bring upgrades to try and make it better."