Piastri has arrived at his home race in Melbourne in a much stronger situation than was the case on his debut last year, when the Australian GP was only his third F1 start and the Woking team was struggling with an uncompetitive car.
In his rookie season he also adopted a strategy of playing himself in on Fridays and building up his pace over the course of a weekend.
This season he has been pushing Norris hard from the off, logging eighth place in Bahrain and fourth in Jeddah.
"He continues to get faster and faster,” said Brown when asked about Piastri’s progress. “Obviously, we're two races in, but what we're seeing is he's got his rookie stripes off now. And so on Fridays he gets on the pace right away.
“He doesn't really make mistakes. He's extremely fast. I think for the first two races of the year, it's the closest driver pairing in the field.
“And that's exactly what you want as a team. And I think they're pushing each other, they're pushing the team. So I'm very excited about our driver line-up for the foreseeable future."
Brown acknowledged that Piastri is more relaxed in Melbourne than he was this time last season.
“Last year was also a very difficult start to the year,” he said. “So in addition, add in the pressure of being a rookie and then coming to your first home race and you're also in a race car that's not that strong.
“So I think he's now had a year under his belt. He knows what to expect. He's got a much better race car that he's sitting in, and so he's definitely enjoying it. And nice to see him maturing.
“He's already a mature young man, but you can definitely see a year on he's got a higher level of confidence because he knows what to expect. And I think that'll just drive even better performance with the helmet on.”
Last year, McLaren scored no points in the first two races, and the team lay 10th and last in the world championship at the start of the Melbourne weekend.
“It's a lot better this time around,” said Brown. “This was the first race where we scored points last year, and even then we inherited quite a few after the incident at the very end of the race.
“All the men and women at McLaren are continuing to do a fantastic job. I feel like we've kind of picked up where we left off the second half of last year. The field has never been closer, so we need to continue to push hard.
“But I think we've designed and developed a very strong racing car that will hopefully get stronger, but we know the other nine teams are not sitting still. Our drivers are doing a great job. We've got a lot of harmony in the racing team.
“So I feel we're in a really good place to continue to improve and push forward, and I’m pretty excited for a lot more racing this year."
