McLaren-Honda have become the first team to pick up engine penalties in 2017 after Stoffel Vandoorne was hit with a 15-place grid drop in Russia for already exceeding engine limits.
Despite the season only entering its fourth race weekend out of 19, persistent unreliability on Vandoorne's MCL32 has meant the Belgian rookie has already used more than the maximum amount of penalty-free parts for two of the six areas that make up an F1 power unit.
An MGU-K failure in Practice One in Sochi triggered more power unit changes for Practice Two, as McLaren fitted a fifth MGU-H and fifth turbocharger of the season.
F1's rules dictate that the first time a driver uses a fifth engine element they will go back 10 places on the grid, with five further places added for every additional fifth element used. Vandoorne will therefore take a 15-place grid drop.
But such is McLaren's lack of competitiveness that Vandoorne is highly unlikely to be able to serve all the penalty places, with a back-of-the-grid start on Sunday set to be the net result.
Vandoorne missed the first 20 minutes of P2's running while McLaren's mechanics completed the latest round of changes. The 25-year-old has endured a torrid start to his first year of F1 and was unable to even take the start of the last race after a succession of Honda MGU-H failures in Bahrain.
New MGU-H units with reliability developments had been fitted to both Vandoorne and team-mate Fernando Alonso's cars ahead of Friday practice.
Will Ferrari stay ahead of the pack in Sochi? Watch the Russian GP weekend with Sky Sports F1. The race begins at 1pm on Sunday April 30. Check out all the ways to watch live F1 on Sky Sports for subscribers and non-subscribers - including a NOW TV day pass for £6.99!