Fernando Alonso's future with Ferrari is almost certainly in serious doubt.

Some Spanish media sources continue to insist that the frustrated Spaniard is not interested in leaving the crisis-struck Italian team for McLaren-Honda, or even reigning world champions Red Bull.

But dominant Mercedes could be another matter.

Magnussen's future in doubt?

Still, the latest rumours suggest McLaren could now be heading towards a highly-experienced lineup of Alonso alongside Jenson Button to spearhead the new Honda era.

That would leave rookie Kevin Magnussen in the cold.

All of a sudden, the young Dane is admitting his future might not be secure.

"It would make no sense to go from McLaren to a smaller team," Magnussen is quoted by Russia's f1news.ru.

"If I do not manage to be successful with McLaren and meet their expectations, then I'm not good enough to be world champion anyway."

What's going on at Scuderia Ferrari?

At the very same time, strong signs that not all is well between Alonso and Ferrari's new boss Marco Mattiacci are becoming ever more concrete.

I have been asked to lead this and not everyone can like it. Marco Mattiacci

Authoritative reports are quoting Mattiacci as having given unusual answers to very direct questions about Alonso's position at Ferrari after the Singapore Grand Prix.

"Fernando is still with us in 2015? At the moment, yes," he said.

"He has a contract until 2016, but there is an ongoing discussion also about how we will define the relationship."

Italy's respected and specialist La Gazzetta dello Sport on Monday claimed Alonso has now "expressed his intention to leave Ferrari" after conditions placed on his continuing position were not accepted or met.

The report quoted Mattiacci as saying: "We must have the courage to change and not rest on the laurels of the past.

"I have been asked to lead this and not everyone can like it," he added.

The Spanish sports newspaper Marca, however, quoted Mattiacci as insisting in Singapore that "Nothing has changed in my relationship with Fernando this weekend".

But, clearly referring to the management upheavals at Maranello this year, he also said: "I do not know any company that makes such profound changes where everyone can be happy about it.

"Some like it and some do not. But sometimes you have to have the courage to change."

More signs of the clash between Mattiacci and Alonso could be detected in their assessment of Ferrari's performance in Singapore.

Mattiacci claimed the team has made clear progress since Monza.

"We had the pace of Red Bull - it is clear that the car has improved," said the Italian.

But Alonso said: "My teammate was 45 seconds behind me."