Jenson Button says the resurfaced Hungaroring circuit made him "feel like an amateur" on several occasions on Friday due to its "unusual" grip levels.
The Budapest circuit has been re-layed this year, making it less bumpy than in previous years. Friday's opening three hours of practice saw several drivers struggling for grip and Button admitted it would happen out of the blue.
Asked how the circuit was feeling, Button said: "Yeah, good. The circuit is fun to drive. There's quite a bit of grip but the difference between grip and no grip is massive, so if you get a slide the tyre suddenly falls off a cliff and lose every bit of grip you have and feel like an amateur trying to gather the car back up because suddenly it doesn't work if you put too much load into it. So it's very unusual.
"It's strange because you don't feel it coming and if the best drivers' in the world can't feel it coming it's unusal. It's a mixture of the asphalt and the tyres, just getting them into a situation where they work on the asphalt."
Button finished the afternoon practice session in eighth position, one place behind teammate Fernando Alonso as McLaren enjoyed an encouraging Friday.
"Pretty happy with how the car feels. Long run, low-fuel run, pretty good. It's tough round here at the moment though with the way the tyres work.
"We're pretty close in the middle of the field, but we were seventh and eighth. Everyone behind us is very close - the fight is definitely behind, not in front. It's relatively good feeling with the car around here. I like the way it's smoother here, it works for us, definitely."