Lando Norris' world championship bid hangs in the balance with the British driver disqualified from the Las Vegas Grand Prix.
Norris finished runner-up to Max Verstappen in Sin City, but was called before the stewards for breaching the regulations.
Norris’ McLaren team-mate Oscar Piastri also saw his fourth-placed finish chalked off, with the rearmost skid on both McLarens less than the required thickness.
Norris was expecting to head to the penultimate round in Qatar next weekend with a 42-point lead over Red Bull’s Verstappen with just 58 points left to play for.
But the disqualification sees Verstappen trail Norris by just 24 points, changing the complexion of the title battle. Piastri is also now 24 points back following his disqualification.
Norris and a McLaren team representative visited the stewards at 23:45 local time (07:45 GMT) on Saturday – more than two hours after the chequered flag fell.
Earlier this season, Lewis Hamilton was disqualified from the Chinese Grand Prix after the rearmost skid on his Ferrari was less than the 9mm minimum thickness required.
On the track in Vegas, a mistake by pole-sitter Norris at the opening corner dropped him to third behind Verstappen and Mercedes’ George Russell.
A flustered Norris re-joined the circuit and then came within inches of colliding with Verstappen, and in his desperation to avoid a tangle, allowed Russell to draw alongside his compatriot and blast clear.
Piastri was fortunate to avoid damage after he banged wheels with Liam Lawson while Gabriel Bortoleto wiped out Lance Stroll and Lewis Hamilton, who started 20th and last following a nightmare qualifying session, navigated his way through the mess to make up eight places.
Verstappen resisted the early advances from Russell, and was two seconds clear of the Mercedes man, who was the first to pit on lap 17.
That briefly promoted Norris to second only for the championship contender to fall back behind Russell when he stopped for new tyres four laps later.
Verstappen was able to come in for tyres and keep his lead, and then the attention turned to Norris and whether he could clear Russell.
Russell was struggling to keep up with Verstappen and offered little resistance to Norris, who breezed ahead on the Las Vegas Boulevard on lap 34. The Dutchman’s lead, though, never came under threat as he crossed the line 20 seconds clear.
Kimi Antonelli finished fourth, but a five-second penalty dropped him behind Piastri. Charles Leclerc started ninth and finished sixth, four places ahead of Hamilton who claimed a single point on another weekend to forget for the seven-time world champion.
