Jenson Button says McLaren can at least take heart from the "massive improvement" it showed on the first day of testing compared to 2015.
Last year McLaren managed just 79 laps across the four days of the first test at Jerez as the team struggled with its new Honda power unit. Despite changes being made to the engine to address a number of weaknesses from last year, the team hit the ground running today by completing 84 laps on the opening day in Barcelona.
"We did 84 laps so it was a massive improvement on last year," Button said. "Last year it took us the whole test to do that."
Asked if the car itself is any good, Button remained cautious, replying: "I don’t know yet.
"It goes around which is a start and you need that first. There were no negative bits to the car and today has been all about system checks and trying new things as there are lots of differences with this car and the engine.
"The standout today has been the deployment of power has been very good and consistent, much better on longer runs than last year which is good. Obviously it shows other weaknesses in the car which we still need to improve but it has been a good day.
"Outright pace who knows, you look at the times you’d say we’re miles away but we haven’t been going out to set a lap time. Every lap I’m doing different things with the steering wheel and my engineer is always talking to me so there are so many things that we are trying out, electrical things, which is very interesting so not a bad day."
Report: Vettel tops opening day of testing as Mercedes racks up mileage
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GALLERY: Pre-season testing day one
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