Mercedes has officially decided its championship leader Kimi Antonelli will start from the back of the grid at the upcoming Italian Grand Prix after it decided to give the Italian a new power unit, exceeding his allowance for the year.
Drivers are allowed to use up to four power units for the season, but Mercedes' reliability woes over the first half of the campaign meant it has always been a question of when, not if, its drivers were going to exceed that allowance and take a grid penalty. Antonelli is currently already at the limit with his V6 and exhaust system, while Russell has no more room for either a combustion engine or turbocharger.
