Schumacher? Ocon? Wehrlein? Who will partner Kvyat at Toro Rosso?

Esteban Ocon would have to be released from his Mercedes junior deal in order for Toro Rosso to consider him for a 2019 race seat, Dr Helmut Marko has said. The Frenchman is facing the prospect of sitting out the 2019 season after seeing offers from Force India, Renault and McLaren fall through.

Ties to Mercedes put McLaren off signing Ocon, who saw an offer from Renault withdrawn after they confirmed the signing of Daniel Ricciardo, while Lance Stroll's likely move to Force India to follow his father Lawrence – who now owns the team – has cost Ocon his current seat.

Williams are reported to have demanded discounted power units in 2019 if they are to put Ocon into the team – where Robert Kubica is favoured to partner Sergey Sirotkin next year.

Toro Rosso confirmed Daniil Kvyat's return to the team on Saturday at the Russian Grand Prix, but Brendon Hartley is far from secure in the second seat – which could open the door to Ocon, albeit with some help from the Silver Arrows.

"We have a seat, Mercedes doesn't have a seat," Marko told Sky Sports. "If he's free from all contracts we could discuss it, I mean all contracts."

One driver who has been freed from Mercedes duties is Pascal Wehrlein, and Marko says his release has made him a candidate for the role.

"It's a different story now, yes," he told Motorsport.com. "We haven't made any decision. He's on a long list."

Dan Ticktum looks set to miss out on his hopes of taking the seat after falling behind Mick Schumacher in the European Formula 3 fight and then publicly airing suspicions about his rival, as well as lashing out to fans on social media.

Could the son of seven-time world champion Michael Schuamcher be in the frame, though?

"No, definitely not," said Marko. "I think it's too early for him. Let's see what happens in F2."

Wehrlein could be the most likely to sign, having been released from his Mercedes deal earlier this month, however the situation there is also tricky.

"My understanding is he's off to do Formula E next year," Red Bull team principal Christian Horner told Motorsport.com. "That's a discussion that we'll have internally.

"There are numerous options available. I think we've got plenty of time. I don't think we need to be in a rush."

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