Lando Norris and Sergio Perez have criticised the track at the first Miami Grand Prix after several Formula One drivers struggled with the surface in the opening practice sessions.
McLaren's Norris took P6 after Friday's second session but was far from happy with race conditions.
"It is extremely tricky. It is very bumpy in some areas, which is not quite what we were expecting," Norris said.
"I think everyone was expecting it to be very smooth and beautiful, but it's not," he added.
Alfa Romeo's Valtteri Bottas spun backward into the tyre barrier at Turn 7, damaging his car's rear wing in the first practice session, while Ferrari's Carlo Sainz Jr. crashed into Turn 14.
"The surface is very tricky as well because you go off line anywhere and it is pretty much game over and you end up in the wall, so it [is] punishing, let's say," Norris said.
"That is why you have seen quite a few people ending up in the barriers. I feel like it isn't going to be great for racing now.
"That is the negatives, but the positives are it is still a good track," he added.
Red Bull's Sergio Perez agreed with Norris's concerns.
"I am really disappointed there is no grip off line. It's a shame because I think the racing will be bad due to that. As soon as you try to go off line, there is no grip," Perez said.
"It's wet on that side. It feels very gravelly. Racing will be hard. I think it's going to be an interesting race. We are all in the same boat. We don't know exactly where we are," he added.
Red Bull team principal Christian Horner said drivers would have to find a way to handle the corners.
"There's only really one line. You go off line and there's zero grip. That's going to make racing a little bit tricky, but they are finding their way into it and finding the balance and setup compromise for the types of corner that you've got here. It's quite challenging," he said.
George Russell of Mercedes was on top of the timesheets with the fastest lap in second practice, 0.106 seconds faster than Ferrari's overall leader, Charles Leclerc.