Mercedes has officially decided its Formula 1 world championship leader Kimi Antonelli will start from the back of the grid at the upcoming Italian Grand Prix after it decided to give him a new power unit, exceeding his allowance for the year.<br>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 ...<a class='more' href='https://www.autosport.com/f1/news/antonelli-set-for-italian-gp-grid-penalty/10848914/?utm_source=RSS&utm_medium=referral&utm_campaign=RSS-ALL&utm_term=News&utm_content=uk'>Keep reading</a>