Daniil Kvyat was hit by a brake duct problem which halted Red Bull's running for a spell during the first day of the second test.
In the morning session Kvyat returned from a run with smoke emerging from the rear of his car, with Red Bull checking the problem before pulling the RB12 back in to the garage. Kvyat said it was just a small issue with the brake ducts which the team was careful with before resuming running.
"Yes we had a little issue with a brake duct, and we took a little bit of time to understand it and sort it out," Kvyat said. "But the guys did a good job because the rest of the day there was absolutely no issues.
"The guys sorted everything out, so it should not be a problem anymore."
And Kvyat says he feels ready for the first race of the season in Australia despite the loss of running on Tuesday.
"Obviously this last day that we have left would be good to make as good use of as possible. We have done quite a good bit of work until now. There are some other things we still have to go through in the last day of testing, but I am sure we can make up for it."
Despite his optimism, Kvyat remains wary that Red Bull has to work to ensure it knows how to get the maximum out of its car by the first race.
"Generally as the car has not changed too much - for everyone including us - but yes I think there is progress, which we still have to try to extract everything out of this potential progress. I am still calling it [potential] because the real progress we will see in Melbourne and the first couple of races. We are standing in a good place; as always it is all about how we put things together."
REPORT: Mercedes starts to show pace on day one of final test
GALLERY: Second Barcelona Test
AS IT HAPPENED: Second 2016 pre-season F1 test from Barcelona
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