McLaren announced ahead of the Spanish Grand Prix that Marshall, who is a former chief designer at Red Bull, will be joining it at the start of next year as technical director of engineering and design.
His signing comes as part of a major recruitment drive that McLaren has unleashed to ensure it makes the most of a new wind tunnel and simulator that are coming on tap in the next few months.
After a difficult start to the 2023 season, with its MCL60 lacking the performance hoped for, McLaren is pushing hard to find gains in the short term but knows there are huge opportunities over the long haul.
For Norris, the Marshall news was something that he is extremely excited about as he has faith it points to better things down the line.
Asked what he feels Marshall will bring to the squad, Norris said: "Just knowledge, expertise. He's been at Red Bull for many, many years, he's seen a lot of success with the team.
"He's been with some of the best minds within Formula 1 and he's definitely part of that group.
"So, brains and lap time I guess are the two big things. He's a big person, a big signing for us as a team, so I think someone that a lot of people within McLaren will look up to, and respect and so on.
"It is also a good step for us as a team to keep this drive forward, continuing to add performance and expertise too."
As well as capturing Marshall, McLaren has embarked on a major reshuffling of its technical department in the wake of the departure of former technical director James Key, who has since joined Sauber.
The squad thinks its new approach of having three heads – Marshall on design, Peter Prodromou on aerodynamics and David Sanchez on car concept – will be a boost in helping deliver a better car.
Norris, whose own future at McLaren has been the subject of speculation amid its current competitive struggles, says he has total faith in the efforts being made by CEO Zak Brown to improve things.
Asked how much belief he had in Brown, Norris said: "I would say a lot. Even more now than in the past.
"I guess I would never want to say that I have no belief, and I never have said it and probably won't, but definitely since the last few changes, there have been a lot of good things coming from that, both in terms of mood, atmosphere, but at the same time, also performance and things to look forward to in the future.
"Not everything is purely direct in Formula 1, a lot of things take time, so I guess you have that part of it too, but definitely things have taken a step forward. So, I can easily confirm that and say it with confidence."
