BUDAPEST, Hungary — Oscar Piastri was left furious after a collision with Williams driver Carlos Sainz while attempting to lap him cost the McLaren driver any chance of victory at the Hungarian Grand Prix, with the Australian branding Sainz's lack of awareness "unacceptable."

Piastri had been leading the opening stint of the race from teammate Lando Norris and was in contention for a first win of the 2026 season. But his hopes were dashed after his second pit stop when he made contact with Sainz at Turn 2 while trying to lap the Williams driver, who was battling Fernando Alonso for 16th place.

The incident was compounded by a failure of Formula 1's automated blue flag system, which notifies drivers they are about to be lapped. Race control was forced to rely on marshals waving flags and manual light panel activation instead.

Piastri let his anger boil over on team radio, telling Sainz to "get out of the f—ing way you idiot" and asking if he was "f—ing stupid or what." Speaking to reporters after the race, his fury had not subsided.

"I knew there were blue flags, but there were blue flags on all the marshal signals, I was right behind him for a sector," Piastri explained. "I couldn't believe what happened. Getting crashed into by a lapped car is never one of the things you expect that can go wrong in your race, and today it was, so I don't really care if he didn't see me. The fact that he didn't and no one told him, or there was a lack of complete awareness, is unacceptable."

Sainz, who received a five-second time penalty for causing the collision, defended his actions by pointing to the blue flag system failure. "I had no idea I was about to get lapped, and on top of that, I was in a big fight with Fernando trying to undercut him into the corner," Sainz said. "I wouldn't have expected Oscar to be there, and even if he was there or I would have expected he was on my dead spot on the angle, so it was impossible honestly from my side to avoid it."

Sainz added that while he felt sorry for Piastri, he thought he had "a pretty good excuse for what happened" and suggested Piastri could have been "a bit more careful" given he was fighting for podiums.

Piastri was unimpressed by that reasoning, noting that Sainz was fighting Alonso "like it was (for) the world championship." He added pointedly: "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, maybe you should look in the mirror a bit."

The collision cost Piastri a couple of seconds as he grappled to regain control of his car. Those seconds proved decisive: when Norris emerged from the pits on Lap 40, he took the lead ahead of Piastri. Piastri ultimately retired with 15 laps remaining due to a gearbox failure.

While Piastri initially seemed to question McLaren's strategy on the radio — snapping "Oh mate, don't f—ing talk to me now" when told about the lost time — he later clarified his anger was directed at Sainz, not the team. "We wanted to cover off (Lewis) Hamilton, which was perfectly normal," Piastri said. "Without getting crashed into, I would have been ahead of Lando still. So from that side of things I was fine."