Listen to this article Russell finished Friday’s practice running at the Miami International Autodrome with the fastest time, but conceded he did not really understand where Mercedes’ pace had come from after its difficult start to the season. Mercedes trialled a change in set-up on Russell’s car in final practice before going back to the previous configuration for qualifying, only for him to drop out in Q2 in 12th place. Russell’s best lap in qualifying was two tenths of a second slower than what he managed in FP2. “It’s definitely a surprise, but after driving the car and experiencing how it felt, it’s no surprise,” Russell said. “Today, it felt like a totally different beast. We had loads of porpoising today, and we don’t really understand why, and ultimately, that was the difficulty. “It’s the first time I’ve ever felt it all the way through a corner. Through Turn 4 and Turn 5, it was just bouncing through it all, and then it’s all in the braking zones. “It’s a shame, because …