Lewis Hamilton is facing a possible grid demotion after breaching a sporting regulation in morning practice at Interlagos on Friday.
The British championship leader, along with Jenson Button (Honda) and Takuma Sato (Super Aguri), will all be investigated by the stewards after the afternoon session for allegedly breaching article 25.3 relating to wet weather tyres, BBC Radio Five Live said.
It is claimed that the trio used two sets of wet tyres on Friday morning, where the rules say only one set may be used.
Article 25.3 reads: “No driver may use more than one set of wet and one set of extreme weather tyres during P1 and P2”.
BBC Radio said a demotion of five grid positions is a possible sanction, but the stewards may also consider a solely monetary penalty.
With just Sunday’s Brazilian grand prix to go in 2007, Hamilton is four and seven points ahead of Fernando Alonso and Kimi Raikkonen respectively in the drivers’ classification.
Brasil GP, first free practise
1 K. Räikkönen Ferrari 1:19.580 9
2 F. Massa Ferrari 1:20.062 10
3 H. Kovalainen Renault 1:20.829 19
4 N. Rosberg Williams 1:21.064 14
5 L. Hamilton McLaren 1:21.121 10
6 R. Schumacher Toyota 1:21.243 22
7 S. Vettel Scuderia Toro Rosso 1:21.598 22
8 M. Webber Red Bull 1:22.104 12
9 J. Trulli Toyota 1:22.104 26
10 V. Liuzzi Scuderia Toro Rosso 1:22.250 17
11 R. Barrichello Honda 1:22.434 23
12 J. Button Honda 1:22.477 22
13 D. Coulthard Red Bull 1:22.667 16
14 T. Sato Super Aguri 1:22.929 19
15 A. Sutil Spyker F1 1:23.248 30
16 K. Nakajima Williams 1:23.261 26
17 A. Davidson Super Aguri 1:23.551 20
18 S. Yamamoto Spyker F1 1:24.366 25
19 N. Heidfeld BMW no time
20 R. Kubica BMW no time
21 F. Alonso McLaren no time
22 G. Fisichella Renault no time
