Lando Norris topped the times ahead of his team-mate Oscar Piastri as McLaren finished a dominant one-two in Friday's second free practice ahead of this weekend's Belgian Grand Prix.
The duo, who secured a front row lockout in qualifying at last Sunday's Hungarian Grand Prix, set the pace again ahead of series leader and three-time champion Max Verstappen of Red Bull.
The Dutchman faces taking a 10-place grid penalty for Sunday's race after his team fitted him with a new engine, taking him beyond the permitted limit of four units for the season.
Norris clocked a best lap in one minute and 42.260 seconds to outpace Piastri by 0.215 seconds and Verstappen by 0.217, meaning they were separated by only 0.002 seconds after lapping the 7.004-kms circuit, the longest on the calendar.
In cooling conditions, with rain threatening, the Ferraris of Charles Leclerc and Carlos Sainz were fourth and fifth ahead of George Russell of Mercedes and Alpine's Esteban Ocon, who it was announced Thursday will switch to Haas next year.
