Briton Lewis Hamilton complained that people on the pit wall were dropping debris on his head while he was driving his McLaren to a fifth place finish in Sunday's Monaco Grand Prix.
The 27-year-old Englishman said it happened several times as he completed the 78-laps race won by Australian Mark Webber of Red Bull.
Hamilton said: "The guys hold the pit boards over the track and two or three slips fell out and hit me in the front of the helmet.
"I was like 'guys this is getting ridiculous' as they kept dropping them and dropping them."
It was a disappointing race for Hamilton who started third but lost places, notably in the pits again.
"It wasn't the best result, but this is motor racing," he said.
"I really dislike going backwards, but we still go away with some points.
"There are many races ahead of us and we still need to keep pushing. My start was one of worst starts I've had in a long time.
"I don't understand why it happens when two guys next to me and those behind us got perfect starts.
"I was fortunate not to get caught up in the crash. We do thousands of starts, it shouldn't be a problem."
Hamilton was unable to keep up with Webber or German Nico Rosberg of Mercedes at the start and in the opening stint - and was then passed by old rival Spaniard Fernando Alonso of Ferrari in the pit-stops.
He was also passed 'off the track' by defending double world champion Sebastian Vettel following his Red Bull crew's fast pit-stop that allowed him to rejoin ahead of Hamilton, the German having executed an alternative strategy to perfection after starting ninth.
With McLaren team-mate and compatriot Jenson Button retiring eight laps from the finish, the result signalled not only disappointment for Hamilton, but his team.
They have not had a podium finish since the Chinese Grand Prix in April and appear to have lost all their early-season momentum.
"I think the team have definitely got some work to do because we are falling behind race by race. The others are picking up some serious pace," he said.
"If we're not lucky then it will fall away from us."
He also grumbled about yet another costly pit stop.
"I don't know how long my pit-stop was, but I lost quite a lot of time. I just wasn't able to really keep up with Alonso, and Sebastian got me through his pit-stop and then it didn't seem possible to overtake."