Nico Rosberg could lose his second place in the British Grand Prix as a result of radio messages exchanged with his engineer late in the race.
While trying to close down team-mate Lewis Hamilton, Rosberg suffered a gearbox problem with seven laps remaining and took to team radio to report the issue. He was immediately given a setting to change to counteract the problem, while also being informed to "avoid seventh gear" by his race engineer.
Rosberg then replied: "What does that mean? I need to shift through it," which resulted in his race engineer confirming he could shift through to eighth gear.
The stewards confirmed Rosberg would be investigated after the race for the radio messages, which will require him to see the stewards. The FIA has been clamping down on which radio messages are permitted to drivers this season, with Silverstone seeing the restrictions tightened further.
Rosberg finished in second place, 1.3s ahead of Max Verstappen and 6.9s adrift of Hamilton. As it stands, Rosberg holds a four-point lead over his team-mate in the drivers' championship.
"It was a very critical problem, I was stuck in seventh gear and was about to stop on track," Rosberg said after the race. "So they told me to change the default to try and fix it."
Asked if he's confident the message was within the rules, Rosberg replied: "Yep."
In Austria last week, Rosberg was hit with a 10-second time penalty for causing a collision with Hamilton on the final lap, although it did not change his fourth-place finish in the race.
The German was also investigated after qualifying for a slow lap in Silverstone, but escaped punishment.
RACE REPORT: Hamilton beats Rosberg and Verstappen in British GP
AS IT HAPPENED: British Grand Prix
FEATURE: Home sweet Home - Eric Silbermann on Silverstone
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