Christian Horner says the Australian Grand Prix offered proof that Renault has made a step forward with its power unit this year.
Red Bull is running TAG Heuer-badged Renault engines this year after attempting to cut its ties with the French manufacturer in 2015r. The team spent much of last season criticising Renault, but after finishing fourth at the first race of 2016 Horner praised the step in performance over the winter.
"The PU has definitely made progress over the winter," he said. "There is still a long way to go, but it is great that, particularly in race conditions, there has been some progress in performance. Hopefully the guys will take back a lot of encouragement that they are going in the right direction."
Horner is confident Red Bull has one of the best cars on the grid this year.
"Here at this track we certainly had the third fastest car. Particularly in the race. It is encouraging. It is not where we want to be, and obviously we are focused on moving forward, but it is encouraging that the characteristics of the car have continued from last year and evolved, and we have a very good product to work with."