Daniel Ricciardo admitted his set-up programme went in the wrong direction on his final day of pre-season testing with Red Bull Racing.
The Aussie's complaint wasn't about the mileage - 128 laps - but rather the team's direction as it sought to evolve its RB13.
Ricciardo race simulation Thursday afternoon was also hampered by a several red flag periods which interrupted his flow. Overall, he ended the day sixth on the timesheet.
"I wish we were sandbagging a bit more," laughed Ricciardo.
"Today we weren't quick. I would say day one of this week's test we looked more competitive, probably within two or three tenths of the pace, but today it was a lot more.
"I thought that we'd come a fair way after day three in the car, for me, and then day four in the car, for me, today, but it felt like we probably didn't go that extra step forward.
"I think the progress was good and then today we got a little bit confused, with some set-up things. Hopefully we have some answers tonight."
Ricciardo is hoping Max Verstappen's final day in the car will bring its lot of understanding and knowledge to enable an upgraded RB13 to make its way to the grid in Melbourne in two weeks.
"I think in Melbourne we're going to see a little bit from both sides, from the power unit and the car, which will have some more aero bits on it," said the Honey Badger.
"Max had a bit of a troubled day, but my day was pretty clean. It's still a little bit hit and miss, I guess, but I feel like come race day we're going to be in a better position."
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