The Spaniard finished some 36 seconds adrift of Red Bull victor Sergio Perez in Jeddah to clock sixth place, one spot ahead of team-mate Charles Leclerc - who was recovering from a 10-place gird drop.
That penalty was earned for a change of the control electronics unit after Leclerc retired from the Bahrain season-opener, while Sainz was fourth a fortnight ago as Ferrari struggled with its tyres.
