Max Verstappen was comfortably fastest in second practice for the Belgian Grand Prix, with Charles Leclerc finishing a full eight tenths of a second back.
The two championship rivals will take grid penalties for exceeding power unit parts allocation, but the Dutchman managed to send out a warning nonetheless with his performance.
Verstappen managed to win in Hungary despite starting down in 10th, and his time of 1:45.507 showed he could be poised for another impressive fightback on Sunday.
Lando Norris and Lance Stroll surprised by finishing with the third and fourth fastest times, while Carlos Sainz and Sergio Perez, who will try to lead the way for Ferrari and Red Bull this weekend, finished P5 and P10 respectively.
One positive for Verstappen and Leclerc is that Norris, Mick Schumacher, Esteban Ocon and Valtteri Bottas will also take penalties, meaning they could start further up the grid with a strong showing in qualifying.
As for Mercedes, the Silver Arrows lacked pace on the opening day of practice, with Lewis Hamilton and George Russell settling for P6 and P9 respectively.
However with Friday’s running hampered by rain and cold temperatures, the timesheets are expected to be much closer when qualifying takes place on Saturday.