Norris collided with team-mate Piastri as they fought for fourth place in the closing laps of Sunday’s Canadian Grand Prix.
Norris accepted full responsibility for a coming together he said made him look foolish and leaves him 22 points behind Piastri in the battle for the drivers’ title. Norris retired from the race while Piastri was able to take the chequered flag.
“This may have an impact in terms of his confidence,” said Stella.
“We will have conversations, and the conversations may even be tough, but there’s no doubt over the support we give to Lando and over the fact that we will preserve our parity and equality in terms of how we go racing at McLaren between our two drivers.
“The situation would have been different if Lando did not take responsibility and apologise.
“Lando will have to show his character to overcome this kind of episode and make sure that he only takes the learnings to become a stronger driver.”
Norris was already on the backfoot heading into Sunday’s race following two mistakes in qualifying which left him seventh on the grid.
He drove well to bring himself back into contention only to misjudge the move on Piastri which again raises questions over his credentials as a legitimate championship contender.
Nico Rosberg, who competed against Lewis Hamilton at Mercedes for three seasons – eventually beating the British driver to the world title in what would prove his final act in the sport in 2016 – believes Norris is facing a dark period.
Reflecting on his own mental battles as he duelled for the title, Rosberg told Sky Sports: “It becomes a little bit traumatic because you start spiralling negatively down and down, and you get this repetition of, ‘I’m making mistakes, and I’m not good enough,’ and it starts to get to you in your head.
“It can get really dark, and I’ve been through this, especially when you make a mistake like today where everybody can see it, you even hit your team-mate, so your whole team is thinking, ‘What’s going on?’ It will be difficult for Lando to get back out of that.”
Norris will be back in action a week on Sunday in Austria for the 11th round of 24.
But despite his latest setback, he said: “There are plenty more races left. I don’t expect to catch Oscar easily. I have to work hard for it and make less mistakes than I did this weekend.”
