Fernando Alonso faces a hefty Formula 1 grid penalty for Sunday's Belgian Grand Prix as Honda is to again replace his power unit.
The system in Alonso's McLaren sustained a water leak early in the first practice session at Spa-Francorchamps, leaving the Spaniard at the bottom of the timesheets after only completing three installation laps.
Prior to this weekend's grand prix, Honda had spent seven of its development tokens on upgrading the internal combustion engine and turbo compressor.
It meant Alonso and team-mate Jenson Button were handed new power units, and in doing so taking the fifth element of each of the six engine components.
As a precaution following the water leak, the team has decided to swap out the entire power unit to ensure he is "out and running in FP2", according to the Japanese manufacturer.
It means McLaren-Honda has now taken Alonso's sixth of every component of the system - internal combustion engine, turbocharger, MGU-H, MGU-K, control electronics and energy store pack.
The upshot is Alonso will now serve a 35-place grid penalty, although in reality given the rules altered last season, the double world champion will start at the back of the 22-car field.
Honda has confirmed the new system is the same updated specification as the power unit used in first practice.