Robert Kubica is now on his own

As the McLaren-Renault saga and its multi-level implications unfold, one man who appears to have lost out is Robert Kubica.

The Polish driver has been gearing up for a potential F1 comeback, working with and supported by Renault which put Kubica to the task as it assessed his ability to perform at the highest level.

Carlos Sainz' move from Toro Rosso to the French outfit implies that the 32-year-old won't be racing with his former team next season.

According to Motor Sport Magazine's Mark Hughes, Kubica has subsequently been released from his obligations, having been contracted to Renault for his short testing period.

• Sainz remains mum on Renault move

"We understand he has been released from the short-term contract he has been on with Renault since beginning his comeback programme in May," wrote Hughes in his latest column.

"At his request, in order that he might follow up on interest elsewhere for his services (understood to be Williams and Sauber).

"His performance in the Hungaroring test in the current Renault, whilst good, still left question marks about his fitness level, evident in an inconsistency during the long runs. His ultimate speed, on the other hand, was considered highly impressive.

"If Kubica can answer those remaining questions after further training time (and only a test at the appropriate time could really do that), he would be the perfect fit for Williams’ requirements; an A-grade ace who will call it exactly how it is."

At Williams, the final decision rests with Sir Frank who isn't exactly keen on unknown quantities. But as Hughes argues, Kubica does fit the bill, at least on paper.

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