SPA-FRANCORCHAMPS, Belgium — Lewis Hamilton’s grid penalty for the Belgian Grand Prix has increased to a whopping 55 places after Mercedes made further engine changes on Saturday.

The defending Formula One champion and current championship leader was already condemned to start from the back of the grid after picking up a 15-place grid penalty in Friday morning’s first practice and a further 15 spots following another component change in the afternoon.

Given this, Mercedes took the opportunity to make multiple power unit changes — meaning a further and meaningless 25-place drop in a race of 22 cars — with a view to keeping Hamilton’s engine in good shape for the rest of the season.

Grid penalties apply only to the race weekend itself and do not carry over into the next race, meaning that Hamilton’s engine should be in top condition at the Italian GP in Monza next weekend and beyond that, providing he does not encounter further mechanical problems.

Hamilton is joined at the back by McLaren driver Fernando Alonso, who’s taking a 35-place hit for engine changes.

The 55-place drop equals the record grid penalty handed to Alonso at last year’s race in Spa, when his Mclaren teammate Jenson Button also picked up a 50-place penalty under the complex system.

With nothing to gain on the track, or times from rivals to chase down, Hamilton was free to focus on Sunday’s race.

In Saturday’s third and final practice session, he finished fifth but was clearly holding back on speed and his clear priority in the afternoon qualifying session will be to save tires.

Spa is an exceptionally fast circuit with more than 70 percent of the race at full throttle and average speeds around 230 kilometers per hour (143 miles per hour). That will give Hamilton, who is one of the best at overtaking in F1, hope of still earning some significant points.