He was returning a favour: ". . . he let team-mate Valtteri Bottas past into third place, honouring a promise he made earlier in the race when the Finn moved aside to let Hamilton attack the Ferraris" http://www.bbc.co.uk/sport/formula1/40768991
". . . he let team-mate Valtteri Bottas past into third place, honouring a promise he made earlier in the race when the Finn moved aside to let Hamilton attack the Ferraris"
The whole GP was a bit of a joke - the combination of a narrow track and the new wider cars (plus overheating problems from the air turbulence when following another car) meant that overtaking was effectively impossible - a shockingly boring race.