Red Bull team principal Christian Horner insists that he's delighted with how development is going at Milton Keynes so far in 2019.
"We are very happy with the progress that’s being made," he said, referring to ongoing improvements with the RB15 and the progress with the power unit being supplied by new engine partners Honda.
“Considering where we were at the pre-season tests eight or nine weeks ago, to have closed that gap [to Mercedes and Ferrari] and put that performance on the car is really encouraging."
However he was quick to admit that there remained plenty of room for Red Bull to improve over the coming weeks and months.
"We are not at our optimum yet in terms of where we would like to be with these new regulations and construction of tyre," he conceded.
And he acknowledged that the latest tweaks to the F1 technical regulations hadn't worked in favour of Red Bull.
Changes to front wing specifications, and different tyres for 2019, had both been a factor with Horner blaming "probably a combination of the two."
"We were very good on the tyres at the end of last year," Horner said. “Obviously there’s what something like 25 percent less rubber on these tyres, and they are stiffer.
"The concept of aerodynamics that we’ve evolved over the last year’s was very sensitive to the front wing," he added. "So obviously we’re having to re-balance that and re-focus."
As for the power unit, Honda brought a "subtle' upgrade to the last race - the Spanish Grand Prix in Barcelona - which enabled Max Verstappen to take third place ahead ahead of the two Ferrari drivers.
"It’s all about evolution," Horner explained. "Spain was a step forward and hopefully more will follow.
“I think Honda are making good progress," he continued. "Reliability compared to previous years has been fantastic, and performance is strong.
"But of course the others don’t stand still either," he conceded. “Ferrari introduced another engine [in Spain]; Renault introduced another upgrade; Mercedes no doubt around Montreal will introduce another engine.
"Obviously now we have to try and focus on diminishing the gap further to Mercedes.”