Lewis Hamilton and Fernando Alonso criticised the Monaco Grand Prix - saying it was "not really racing" and "the most boring race ever".
Drivers were lapping several seconds off the pace as they managed tyres to ensure they were able to do only one pit stop.
Hamilton said: "We were just cruising around from lap six, literally cruising. So it wasn't really racing.
"If that was exciting for you to watch, no problem."
Alonso, giving his reaction to the race, said: "Extremely boring. This is probably the most boring race ever."
Monaco can often be an uneventful race as a result of the tight nature of the track in the cramped Mediterranean principality, which makes overtaking harder than at any other grand prix.
But the problem was exacerbated this year because drivers were driving slowly to ensure the fragile 'hyper-soft' and 'ultra-soft' tyres, the two softest in Pirelli's range, made the required stint lengths.
Teams do not want to do more than one pit stop because it means dropping behind other, slower cars, which they can then not overtake no matter how much faster they are.
Hamilton, who said the race was "the longest 78 laps ever", added in his BBC Sport interview: "It was a super-unexciting race for everyone."
A fan who was listening in shouted: "Most boring race ever."
Hamilton responded: "Thank God you said it. I thought I was the only one. Wow, it was intensely boring. Oh my God, yes.
"We are driving at high speed, there is not a lot of action, you're just trying to bring it home, for 56 laps. Oh my God, it was long.
"Forty laps to go, I was like, Oh God, please. When it finished, I was like, 'thank goodness'."
Race winner Daniel Ricciardo said that because of the tight nature of the circuit he was able to dictate a slower pace, but added: "I don't think we'll be able to maintain that kind of rhythm on a track like Montreal [the next race].