The 23-year-old, who debuted late last year for Toyota, may also bring Panasonic, according to speculation.
Despite using Ferrari’s engine and gearbox, Sauber is still officially called BMW Sauber F1 Team, and the BMW acronym also appeared on team clothing at Valencia on Sunday and even in tiny lettering on the C29’s nose.
However, the familiar ‘S’ logo, last seen prior to Sauber’s acquisition by the departed German carmaker BMW in 2005, was also on the team clothing.
“The development of the car has seen the team build on the experience gained last year and the improvement in performance over the final third of the season,” said technical director Willy Rampf, also present in Spain.
“However, the new regulations banning refuelling during the race and stipulating a reduced width for the front tyres have required significant changes to the car’s design,” he added.