Max Verstappen says he is not worried about the reliability of Red Bull's Renault engine after hitting trouble on the final day of Formula One pre-season testing.
The Dutch youngster was second fastest as winter testing came to a close at the Circuit de Catalunya, recording the quickest laptime set by the RB13 over the course of the two weeks of testing. A turbo issue on Friday afternoon limited his running to just 71 laps but Verstappen was quick to play down concerns surrounding Renault's rebuilt power unit, despite several problems affecting Red Bull, Toro Rosso and the Renault works team during testing.
"I am not too worried," Verstappen said. "That is what we use testing for to test all the bits and I am quite confident at Renault. They can solve the issues for Melbourne. It is nothing major what is happening, which is good."
Having ended the day 0.8s down on the blistering pace set by Ferrari's Kimi Raikkonen on the same super-soft compound, Verstappen admits Red Bull has work to do on its performance in order to catch up in time for the season-opening Australian Grand Prix in two weeks' time.
"We have to wait and see in Melbourne. The most important thing for us was to check the balance and we definitely improved but it can be better. It was a positive day, the performance is not too bad. We want to improve and we have to improve but it is OK for the moment. Even if we were a little bit faster than what we were today, we always want to improve."
Although laptimes in testing rarely reflect the true relative pace and competitive order for the season, the youngest ever grand prix winner says he does not expect any big surprises come the first race in Melbourne.
"I don't think a massive surprise. In testing you never show everything you can do, it is all about trying to improve the car and get you in good shape for Melbourne. It is not about qualifying lap times. We don't know yet. We have to wait and see. Even after Melbourne you cannot decide that so we just have to remain calm to improve the car."