With 139 laps under his belt, Max Verstappen was happy to conduct a race simulation with "very promising" pace on Friday.
The Dutch rookie, in the car for the penultimate time before his debut season begins, was in action at the Barcelona circuit on Day Two of the final test.
Verstappen covered a marathan 139 laps before an electrical problem curtailed his running late in the day.
He did, however, manage to conduct a race simulation during the afternoon's session and reckons Toro Rosso are looking good.
The 17-year-old, who was seventh quickest on the day, said: "Another good day as we did a lot of laps.
"From my perspective, the most important part was this afternoon's race distance, when the pace looked very promising.
"It was my first time driving the car with the latest updates and they seemed to be working very well and I felt very comfortable with it.
"On Sunday, I get my last chance to drive before Melbourne, so it will be important to get in as many miles as possible, try to improve the car and increase our understanding of the overall package."