Lando Norris cashed in on a fuming Oscar Piastri’s bizarre collision with a backmarker to win the Hungarian Grand Prix.

Australia’s Piastri made the perfect start on Sunday, storming past his McLaren teammate Norris, in pole position, to grab the lead on the third corner.

But Norris later took advantage when Piastri tangled with a dozy Carlos Sainz — as he attempted to put a lap on the Williams driver midway through the race — to land the first victory of his title defence.

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Piastri ran off the road after his front-right tyre made contact with the rear-left of Sainz’s Williams, losing him up to two seconds.

“Get out of the f****** way you idiot, oh my God,” yelled Piastri.

The Australian could not believe what had happened but it allowed Norris, who had stayed out longer before a second change of tyres, to pit and come out ahead.

“Oscar, that’s Sainz that cost us that,” said Tom Stallard, Piastri’s race engineer.

“Oh mate, just don’t even f****** talk to me,” he replied.

Norris emerged in the net lead. He then passed Antonelli on lap 46 before cantering to the chequered flag.

“I’m just happy to be back and see the number one again,” he said.

The collision came after Norris, in hot in his pursuit of Piastri, challenged McLaren to order the Australian out of his way.

Piastri gave up the lead on lap 32 when he came in for his pit-stop, and six laps later his afternoon bizarrely unravelled. Sainz was preoccupied in his duel with Alonso for 15th and ignored the blue flags to ram a mystified Piastri off the road.

Sainz was given a five-second penalty but it would get even worse for Piastri when his gearbox expired with 14 laps remaining. A Virtual Safety Car was deployed and Norris was able to dive in for a third pit-stop and retain the lead.

“We didn’t have blue lights on the steering (wheel) which normally, when we are in fights like that one where we are fighting for position, it helps us to understand whether we’re getting lapped or not,” Sainz said.

“So at this stage, I had no idea I was about to get lapped. On top of that, I was in a big fight with Fernando trying to undercut him into the corner and I wouldn’t have expected Oscar to be there.

“And even if he was there, or I would have expected (Piastri), he was in my dead spot on the angle. It was impossible, honestly, from my side to avoid it.

“Probably a bit better communication would have helped. But at the same time, sometimes it happens.”

Piastri said the episode was “unacceptable”.

“He was fighting Fernando for last place like it was the world championship,” he said.

“It cost me the lead of the race. He’s quite critical of others, and others have given him some stick before for being frustrating on track.

“When you go and do something like that, I think maybe you should look in the mirror a bit.”

Responding to Sainz’s claim that blue flags had malfunctioned, Piastri held firm: “That’s no excuse at all. That’s got to be one of the dumbest things I’ve seen in a race track. I don’t really care what excuse he gave.”

Meanwhile, Max Verstappen finished second, with Antonelli a place back in third, allowing the Italian teenager to increase his title advantage over Lewis Hamilton from 45 points to 50.

Hamilton, who will surely be left questioning Ferrari’s strategy after he stopped for tyres one more time than Verstappen and championship rival Antonelli, finished fourth but a five-second penalty for pit-lane speeding demoted him to fifth behind team-mate Charles Leclerc

George Russell recovered from a nightmare start to finish seventh, but he is now 59 points off the championship pace.

Norris kept the chasing pack behind at the opening corner only to carry too much speed into the next bend, running wide and allowing Piastri to sneak through.

Leclerc, who started between the McLaren drivers, slipped back from second to fifth with Verstappen and Hamilton moving up to third and fourth, respectively.

Hamilton, on the speediest soft tyre compound, set about harassing Verstappen with the Red Bull driver having to defend for his life. Hamilton’s right-front tyre slapped Verstappen’s rear-left through the third bend but both drivers escaped without damage.

For Russell, it was another chapter in his bad-luck story. His new Mercedes engine went into anti-stall as the lights went out, leaving him 19th at the end of lap one. Russell was up to 12th by the start of the 10th lap, and then ninth after his first pit stop.

Unable to find a way past Verstappen, Hamilton moaned: “Max is really slow.” Hamilton attempted the undercut by stopping one lap before Verstappen, and it worked. However, Verstappen caught Hamilton off-guard to snatch the place back at the first corner.

Hamilton was then handed a late five-second penalty for speeding in the pit-lane — in his haste to emerge from his third stop ahead of Antonelli — and he crossed the line only 4.3 seconds ahead of Leclerc to lose fourth place.

“Handing out penalties like crazy,” said Hamilton on the radio, the 41-year-old’s fourth sanction by the stewards in three rounds.

The season resumes in the Netherlands on August 23 — the first of a scheduled 12 rounds still remaining.