Mercedes dominated the final day of F1 preseason testing in Bahrain, posting the fastest times as the season's new rules and cars took center stage. Lewis Hamilton and his team set the benchmark, leaving rivals like Red Bull and McLaren chasing. Fernando Alonso warned that Aston Martin, despite a disappointing start, will soon close the gap, calling it 'a matter of time.' Drivers, however, voiced frustration, with Max Verstappen calling the new cars 'Formula E on steroids' and Lando Norris suggesting fans need a degree to grasp the complex regulations. Mercedes' pace was undeniable, but the Aston Martin gap of four seconds to the leaders remained a stark reminder of the challenge ahead.