Despite Toto Wolff stating that “everything is pointing” to Pascal Wehrlein racing in Bahrain, the German admits it is not yet a done deal.
Wehrlein has yet to complete a grand prix weekend with Sauber after suffering micro fractures to his back when he crashed at the Race of Champions.
His place on the grid has gone to Ferrari third driver Antonio Giovinazzi, who impressed in Australia before having a crash-strewn Chinese GP weekend.
It is not yet known which of the two drivers will line up on Sunday's grid in Bahrain with Wehrlein revealing that nothing has yet been decided.
"For me, the most important is that I can train intensively to ensure a 100 percent performance from my side as soon as possible," he said.
"I will then be well-prepared for my first complete grand prix weekend for the Sauber F1 Team.
"Hopefully this can be in Bahrain but, if not, then we will take the time it needs until Russia to make sure I am completely ready."
However, Mercedes team boss Wolff believes Wehrlein, a member of the Mercedes young driver programme, will be back in the car come Friday's practice at the Sakhir circuit.
"I am only hearing good things about it – that he is feeling better and stronger," he told DPA.
"At the moment, everything is pointing at him sitting in the car in Bahrain."
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