Max Verstappen admitted that an uncomfortable Friday practice at the British Grand Prix was his worst of 2019 as the Red Bull driver followed up victory in Austria with a day of struggle at Silverstone.
Verstappen ended the day seventh-fastest, trailing the McLaren of Lando Norris and his team-mate Pierre Gasly, who also topped the timesheets in FP1.
The Dutchman has almost totally had the measure of Gasly this year, but said strong winds at Silverstone and the new track surface made things difficult.
"Of course with a new tarmac you need to understand the grip levels a bit but it is good," Verstappen said.
"It is a bit bumpy in some places so that's a shame but in general there is more grip. All the drivers like that.
"In general it was quite windy so it wasn't easy and clearly we didn't have a good car balance so that makes it even more difficult.
"I would say this Friday is maybe one of the worst I have had this year, so we still need to work.
"But it's promising that we are still quite close to Mercedes and Ferrari.
"[It was] not the best day. I just didn't have a good balance with the car. I was sliding around a lot and not comfortable. So we still have quite a bit of work to do."