Norris in dream land after epic home win at Silverstone
The beaming 25-year-old Briton claimed his maiden home triumph in stirring fashion to trim Piastri's lead in the drivers' world title race to eight points after the Australian was handed a 10-second penalty for driving erratically while leading behind the safety car.
Piastri was understandably aggrieved at the stewards' decision and requested that McLaren instructed Norris to swap positions with him, but he was told the team would not issue any team orders.
"I don’t really understand it," he said of the penalty meted out after he caused Max Verstappen of Red Bull to overtake him shortly before a re-start that saw the Dutchman slide off-track and drop eight positions.
"I need to look back and see it again because I don’t think I did anything different or anything wrong," he said.
"I mean I did what I did at the first re-start and, apparently, one needed a penalty and other didn’t."
Piastri's misery, after McLaren's fifth 1-2 of the season, was Norris's joy as he celebrated with his family and friends after surviving a testing afternoon of torrential rain, multiple safety car interventions and collisions in treacherous conditions.
'Incredible race'
"It's beautiful," said Norris.
"Everything I dreamed of, I guess. Everything I've ever wanted to achieve. Apart from a championship, I think this is as good as it gets in terms of feelings and in terms of achievement, being proud, all of it.
"This is where it all started for me, I was actually watching on TV many years ago and now thankfully I've been able to have my go.
"An incredible race, stressful as always, but the support from the fans -- it made the difference today so I've got to thank them for it all.
"The last few laps, I was just looking into the crowd. I was just trying to take it all in, enjoy the moment, because it might never happen again.
"I hope it does, but these are memories that I'll bring with me forever. An incredible achievement."
The McLaren drivers congratulated each other and the team, Piastri describing his car as a rocket-ship.
"With all the safety cars and everything, to win by such a big margin is impressive," he said of their 34-second lead ahead of third-placed Nico Hulkenberg of Sauber.
At the midway point in this year's 24-race championship, after 12 races, Piastri leads with 234 points ahead of Norris on 226 and Verstappen on 165 while in the constructors’ title race McLaren lead with 460 to Ferrari on 222 and Mercedes on 210.
It was McLaren’s first home triumph at Silverstone since seven-time champion Lewis Hamilton won in 2008. For Norris, it was a first home win, his fourth win of the year and the eighth of his career.
For Hulkenberg, 37, and in his 16th season, finishing third delivered his long-awaited first podium in his 239th race, but also ended Hamilton's run of 12 podiums in his home event.