Valtteri Bottas is confident Alfa Romeo can make up for lost time in Bahrain having endured a torrid first pre-season test with the team in Spain.
Former Mercedes driver Bottas completed only 54 laps of the Circuit de Barcelona-Catalunya - 12 laps fewer than a Spanish Grand Prix race distance - in 12 hours of running allocated to him by the team.
A myriad of issues across the three days conspired to keep the Finn in the garage but speaking at the conclusion of the test, Bottas said: "The team has made good progress with the C42, even though I wasn’t able to get all the running I would have liked.
"A few technical issues stopped us in the afternoon, but the data we collected during the morning session will allow us to keep working and developing the car.
"Our focus switches to making the most of the time between now and the Bahrain test and maximising our mileage when we get there. I am confident we can make up the time we lost and be fully ready for the season ahead.”
Zhou finds positives despite two red-flag issues
Rookie Guanyu Zhou enjoyed a more positive test, completing 112 laps in the eight hours available to him.
The Chinese driver took control for the morning session and lapped the circuit 41 times, his running time cut short by a spin and a hydraulic leak that saw him trigger two of Friday's five red flags.
“It was a positive day, with quite a bit of running and some good indications until nearly the end of the session," he explained.
"I was able to run with the C3 compound, but unfortunately a spin and a small hydraulic leak meant I couldn’t try the C4 tyres.
"It’s only testing and we can’t really compare what we are doing against the other teams, but the feeling is that we are going in the right direction.
"The most important thing is to work together as a team to make sure we take a step forward ahead of testing in Bahrain.”