Max Verstappen admits Red Bull Racing are playing catch-up to Mercedes and Ferrari as they head for the second round of the season in China.
Verstappen finished fifth behind the top two teams in Melbourne two weeks ago, but was comfortably best of the rest in the first race for the RB13 - a minute ahead of Felipe Massa's Williams in sixth.
The Shanghai International track offers a different challenge to the streets of Albert Park though, with longer corners and a kilometre-long back straight, emphasising horsepower.
But with the gap to Mercedes and Ferrari more than a second in qualifying in the opening round, Verstappen admits Red Bull are playing catch-up.
"It's quite a big gap (to Ferrari and Mercedes)," said Verstappen. "I'm confident that we can definitely close it in the upcoming races to within a second, and then we'll see when we get the bigger upgrades on the engine side.
"For sure, we have to improve, but that's how it is. We're definitely working hard to get new parts to the car as soon as we can, to try to get the pace up a bit, and be closer to the top two teams.
"Behind us, at the moment, I think there's quite a big gap; I think I could have done two pit-stops in Melbourne and still have the same position!
"I think we can just improve the general balance (of the car), it feels pretty good, but we need more load, a bit more grip, and we need more power."