While this weekend’s Monaco Grand Prix might not have had the most exciting racing, it at least provided us with a shake-up from the usual podium finishers. We got to see McLaren’s Lando Norris in third, followed by Ferrari’s Carlos Sainz in second, then Red Bull’s Max Verstappen, who is now leading the Drivers’ Championship, in first.

Aside from reigning champion Lewis Hamilton being stuck in seventh place for nearly the entire race, this refreshing finishing order mainly came about from two things: Ferrari’s Charles Leclerc being unable to start the race after qualifying on pole due to mechanical issues, and Mercedes’ Valtteri Bottas retiring after a cross-threaded wheel nut had been machined onto the car’s axle during a pitstop. Due to how high their positions were before then, these two events essentially bumped the rest of the grid up two positions and left some of the top competitors out of the podium places.

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The interesting thing about the Bottas incident, though, is that over a day later, the wheel nut and its accompanying wheel are still stuck on the axle. The nut is apparently so tight on there that Mercedes won’t be able to remove it until they bring the car back to their factory.

As explained by Mercedes technical director James Allison to Motorsport, “If we don’t quite get the pitstop gun cleanly on the nut, then it can chip away at the driving faces of the nut. We call it machining the nut. It is a bit like when you take a Phillips head screwdriver, and you don’t get it squarely in the cross of the screwdriver. You start to round off the driving face of the screwdriver slots, and then you just simply can’t take the screw out of whatever it is you are trying to take it out of because you have no longer got the driving faces.”

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Essentially, the high-speed wheel gun wasn’t properly seated on the nut, which led to it whittling away at the nut’s two prominent driving “tabs” until it became too rounded off to grab a hold of. According to Allison, the only way to get it off now is by cutting into it with a high-powered drill back at the factory.

As a result of the sub-optimal weekend for Mercedes, Max Verstappen and Red Bull now lead both the Drivers’ and Constructors’ Championships going into the next race in Azerbaijan, which means this season might actually see the first proper title fight in years.