Fernando Alonso complained of being “sandblasted” during first practice, while two punctures and a loose screw forced the FIA into demanding the Interlagos circuit be cleaned after qualifying.
During Thursday's track walk, an undertaking made by all teams to assess the state of the circuit, performance director Tom McCullough reported to FIA race director Niels Wittich that the track was ‘dirty'.
To avoid the prospect of further issues, the track was cleaned following support races staged in between practice and the start of the qualifying session for the grand prix. It led to a 15-minute delay.
Pirelli motorsport director Mario Isola said: “We had a couple of punctures due to debris, and we also found some cuts on the tread.”
Confirming of his intention to inform the FIA of a track clean, Isola added: “I believe the problem is in the pit lane more than on track, but we have to pay attention because we had a couple of genuine punctures on the tread.”
McCullough, meanwhile, revealed two-time F1 champion Alonso was left far from happy with his initial run in FP1, in which he also collected a puncture.
“We always walk the track, we always measure the track to understand the grip level and the state of the track,” said McCullough.
“It was very dirty with the rainwater running across the track, with the mud, you could see that as you went around.
“We always report back to the race director what we think of the track, and we said it was dirty.
“We didn't actually notice any debris, like Mario said, maybe in the pit lane.
“But when Fernando was on track when he did his first run, the first comments he made were about there being lots of stones, and he felt like he was being sandblasted as he was driving.
“We could see the front wing, the front of the car had taken a hard hit.
“We then subsequently ended up with a puncture, unfortunately, on the left-rear tyre, so that curtailed some of his running, and we had to adjust the plan to suit that.”