Jamie Morgan, Guest writer
According to Blick newspaper, Hulkenberg and his manager Werner Heinz are having "sleepless nights".
Pirelli boss Paul Hembery claimed that "some teams went against our recommendations".
What happened to Sergey Sirotkin and the Russian deal?
Bruno Senna now confirms he as in talks with the Sahara Force India team prior to his leaving Formula One to contest the World Endurance Championship with Aston Martin Racing.
Vettel gains another victory but Webber is out after an incident
Bob Fernely: Jules is a significant candidate, along with Adrian.
The German will embark on his seventh season in Formula One with the Swiss outfit.