Formula One:Fernando Alonso put McLaren team-mate Lewis Hamilton in the shade by setting fastest time during the first practice session for the US Grand Prix at Indianapolis.
Alonso, beaten last time out by Hamilton in Canada, set the fastest time during the first practice session as Nick Heidfeld relegated Hamilton to third quickest.
Alonso clocked one minute 11.925 seconds around the Indianapolis Motor Speedway as preparations began in earnest for Sunday's US GP.
The Spanish double world champion was 0.466secs faster than BMW Sauber driver Heidfeld, who had claimed second place in Canada last week behind McLaren rookie Hamilton.
Heidfeld split the McLarens with Hamilton, who had never seen the track before yesterday, managing a best lap of 1:12.628 from his first 21 laps on the famous circuit.
There was more bad news for Ferrari, trailing McLaren in the constructors' championship by 28 points.
Both Kimi Raikkonen and Felipe Massa were outpaced in the opening session by Sebastian Vettel, the 19-year-old BMW Sauber test driver who will make his GP debut on Sunday.
The German teenager is as a replacement for Robert Kubica, who was yesterday stood down by Formula One and race doctors following his spectacular accident in Montreal last Sunday.
Vettel clocked 1:12.869, the fourth fastest of the session, with Raikkonen the quicker of the two Ferraris with 1:12.966, 1.041secs slower than Alonso.
Massa, disqualified last week in Canada for jumping a pit lane red light, managed seventh fastest in 1:13.040, 0.02secs behind the Williams of Nico Rosberg.
Britain's David Coulthard (1:13.159) of Red Bull Racing was eighth fastest, followed by Honda's Jenson Button (1:13.597), with Coulthard's team-mate Mark Webber of Australia rounding out the top 10 (1:13.682).
Super Aguri's Anthony Davidson ran 20th of the 22 drivers in 1:14.632 but managed only 10 laps during the 90-minute session.
Alexander Wurz sat out the session, allowing Williams to give test driver Kazuki Nakajima lap time, while Spyker's Adrian Sutil spun out on the chequered flag lap and was unable to escape the gravel.
Times
1 F. Alonso McLaren 1:11.925 16 laps
2 N. Heidfeld BMW 1:12.391 24 laps
3 L. Hamilton McLaren 1:12.628 21 laps
4 S. Vettel BMW 1:12.869 33 laps
5 K. Räikkönen Ferrari 1:12.966 21 laps
6 N. Rosberg Williams 1:13.020 24 laps
7 F. Massa Ferrari 1:13.040 22 laps
8 D. Coulthard Red Bull 1:13.159 22 laps
9 J. Button Honda 1:13.597 23 laps
10 M. Webber Red Bull 1:13.682 26 laps
11 J. Trulli Toyota 1:13.777 32 laps
12 K. Nakajima Williams 1:13.786 27 laps
13 R. Schumacher Toyota 1:13.819 27 laps
14 V. Liuzzi Scuderia Toro Rosso 1:13.907 28 laps
15 S. Speed Scuderia Toro Rosso 1:13.990 24 laps
16 G. Fisichella Renault 1:14.000 19 laps
17 T. Sato Super Aguri 1:14.037 20 laps
18 R. Barrichello Honda 1:14.052 23 laps
19 H. Kovalainen Renault 1:14.189 18 laps
20 A. Davidson Super Aguri 1:14.632 10 laps
21 C. Albers Spyker F1 1:14.636 28 laps
22 A. Sutil Spyker F1 1:14.810 27 laps