Valtteri Bottas has praised the progress of Mercedes, claiming the W10 feels "completely different" compared to winter testing.
The Finn would dominate Friday practice ahead of this weekend's Spanish Grand Prix, topping both sessions and eventually leading teammate Lewis Hamilton by 0.049s.
It was a result which points to a continuation of the domination which the German manufacturer has enjoyed in 2019, and is certainly a far cry from the difficult early days of testing at the same venue in Barcelona.
"The car felt really good today, completely different to how it was in winter testing, and it seems like our cornering performance has improved," Bottas reflected.
"The balance around the lap is also better, so it looks like we've taken the right direction since the winter."
Also Read:
- Hamilton: Engineer swap is a factor in Bottas' improvement
- Mercedes: Nobody would have predicted four one-twos to start 2019
- Bottas on 2019 results: 'If you work hard, things will start to go right'
Valtteri wasn't getting carried away, however, admitting while the car feels better, it remains to be seen if it is the fastest.
"Today was good, but it's only Friday and Ferrari are very close," he noted. "It feels like we've made a good step forward, but we need to wait and see what tomorrow holds."
Like every team, Mercedes arrives at the first European race with a significant upgrade, but Hamilton concedes it is difficult to make an assessment after just one day.
"It was quite windy on track today and it was a bit tricky with the grip levels on the three different tyres," he commented.
"We got through our programme and now have lots of data to analyse tonight and then fine-tune the car for tomorrow.
"Everyone worked really hard to bring the new package here and a huge amount of effort has gone into it. It seems like it's working, but it's hard to feel it because this track is so different [compared] to the streets of Baku.
"We've got work to do with the balance, but it's been positive for us to be out there," Hamilton concluded.
