McLaren Formula 1 drivers Fernando Alonso and Stoffel Vandoorne are set to start this weekend's Mexican Grand Prix from the back of the field after the FIA stewards confi🔴rmed their grid penalties following power unit changes ahead of practice on Friday.

Alonso and Vandoorne confirmed on Thursday they would be making a number of changes to their Honda power ಞunits ahe❀ad of the race weekend, expecting to receive hefty grid drops as a result in the latest setback for McLaren in a tough season.

The penalties were confirmed by the FIA race stewards at the Autodromo Hermanos Rodriguez during FP1 on Friday, with Alonso dropping 20 ꧋places on the grid after taking a new internal combustion engine, turbo and MGU-H. Vandoorne will drop 35 places after taking a complete new power unit.

"The circuit is not the perfect for our package anyway ,so 𝓀we don’t expect to be super-competitive here," Alonso said on Thursday.

"Maybe it is the best place for the penalty and hopefully we can be better in Brazil and Abu Dhabওi with the new engine."

Va♑ndoorne added: "Hopefully it should be the last grid penalty [this season] but we knew this would be a difficult circuit f🌄or us in terms of performance.

"We were always planning to take a penalty here, to protect us for the last two races, where hopefully we should be more competitive and have mor🏅e opportunities."