The 2021 championship had, by the time the paddock arrived at Silverstone, already curdled into something close to open hostility between Mercedes and Red Bull. Hamilton and Verstappen had traded wins and controversial contact for months, and the rivalry had turned personal enough that team principals Toto Wolff and Christian Horner were sparring almost as fiercely in television interviews as their drivers were on track.
Silverstone hosted Formula 1's first ever Sprint race that weekend, a new format that saw Verstappen win Saturday's shortened contest and line up on pole for Sunday's grand prix, with Hamilton alongside him in second. At Copse — one of the fastest corners on the calendar, taken at close to 180mph — Hamilton went for the inside on the opening lap. Verstappen held his line. The cars touched, and Verstappen's Red Bull was launched off the circuit and into the tyre barrier at extraordinary speed, the impact later measured at 51G. He was taken to hospital for precautionary scans, released the same evening, but did not take any further part in the weekend.
Stewards handed Hamilton a ten-second penalty for causing the collision, served during his pit stop, and Red Bull's fury at what they considered reckless driving by a title rival was immediate and public — Horner's criticism of Hamilton in the race's aftermath was some of the most pointed of the entire rivalry. Hamilton served his penalty, fought back through the field, and won the race anyway, in front of a Silverstone crowd that greeted the result with a level of noise rarely heard even at a British Grand Prix.
The incident became one of the defining flashpoints of the entire 2021 season — not the first collision between the two title contenders, and not the last, but the one that most clearly established the tone of a championship fight that would run, with barely diminished intensity, all the way to its final corner in Abu Dhabi five months later.