A second specification was due to be introduced at the 2018 Canadian Grand Prix, however reliability issues prompted Mercedes to introduce at the 2018 French Grand Prix, naming it as a Phase 2.1 power unit. The third specification was then introduced at the opening round of the 2nd half of the 2018 Formula One World Championship season, the Belgian Grand Prix. For the 1st time in the turbo-hybrid era starting from 2014, Mercedes-AMG F1 M09 EQ Power+ power unit was down on straight line power across the season as compared to the Ferrari 062 EVO power unit used for Ferrari SF71H.