MONTMELO, Spain -- Renault driver Carlos Sainz says he would put money on the gap between both ends of Formula One's field opening up significantly in the remaining three days of testing despite a tight spread on Tuesday.
Just 1.3 seconds split the top 10 drivers as pre-season resumed in sunny conditions at the Circuit de Catalunta after a weather-affected opening test. The limited running last week has delayed schedules, meaning most teams are still not close to exploring the performance limits of their cars.
Despite Sebastian Vettel topping the session with a 1:20.396, Sainz is expecting to see a big drop in lap times by the end of the week.
"If I would have to put my money now I would say it's a coincidence," Sainz said about the small gap. "Not really [representative], the performance of a car nowadays can vary between five to six seconds, so it doesn't mean nothing that we are all [within] a couple of seconds.
"I saw at the end as each car can go up to three seconds faster or three second slower, so not realistic, also the track varies a lot within the day, I found the track very difficult to drive this afternoon, and then getting a bit better in some stages when the wind was coming down, then being very bad again, also when you do your fastest lap time des count a lot."
Sainz believes the grid's 10 teams are still focused on understanding the fundamentals of their cars.
"There's room to improve on everything. Performance, everyone has performance level in the car [to find], also from our side, balance-wise, set-up wise, I said it last week and I say it again, we have big margins of improvements for finding better set-up.
"I'm not worried, I think whenever we start testing we will do it, again today was more about recovering mileage not so much about testing, and hopefully the next few days I start investigating a bit where to go."