It's all change at McLaren next year, with it having succeeded in its long, drawn-out quest to switch from Honda to Renault power for 2018.
Toro Rosso will run Honda engines next year, with Red Bull in line to do the same in the future should Honda's performance improve sufficiently - potentially giving Red Bull the works-engine operation it craves.
But perhaps the most intriguing element of the intertwined deal is the news Red Bull has agreed to loan out Carlos Sainz Jr to Renault for 2018 - and what it now means for his future.