Valtteri Bottas gave a thumbs up to the updates Mercedes has brought to its W10 Silver Arrows after clocking in with the fastest time in both of Friday's free practice sessions.
Like its rivals, Mercedes implemented a series of changes to its 2019 contender ahead of this weekend's Spanish Grand Prix in Barcelona.
While the aero developments appeared relatively minor, with the W10 sporting new turning vanes and a revised mirror concept, Bottas felt the changes had added definitely improved his car's behavior around the Circuit de Catalunya compared to its impressions from pre-season testing.
"It's always an interesting day when you're bringing new parts to the car to get a feel for it and see if they bring the performance they should," said the Mercedes.
"The car felt really good today, completely different to how it was in winter testing, and it seems like our cornering performance has improved.
"The balance around the lap is also better, so it looks like we've taken the right direction since the winter.
"Today was good, but it's only Friday and Ferrari are very close.
"It feels like we've made a good step forward, but we need to wait and see what tomorrow holds."
©Mercedes
Bottas was 0.115s ahead of team mate Lewis Hamilton in FP1, a gap that narrowed to 0.049s in the afternoon session. The reigning world champion had no special complaints to formulate at the end of the afternoon save an observation on the windy conditions.
"It was quite windy on track today and it was a bit tricky with the grip levels on the three different tyres, but we got through our programme and now have lots of data to analyse tonight and then fine tune the car for tomorrow," said Hamilton.
"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 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."
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