Lewis Hamilton has denied insinuating that Red Bull under-inflated Max Verstappen's tyres for Sunday's race at Silverstone.
While Verstappen raced to victory and the two Mercedes struggled with excessive tyre problems, world champion Hamilton said on the radio: "He must have less pressure in his tyres or something."
Former Red Bull driver Robert Doornbos didn't like the sound of that.
"Hamilton is a really bad loser if he's going to assume that," he told Ziggo Sport.
After the tyre problems - including failures - at the first Silverstone race, Pirelli reacted by increasing mandatory tyre pressures for the second.
Hamilton called them "balloons" - but he denied accusing Red Bull of cheating.
"When we start the race we have minimal pressures and they increase during the race," he explained. "With more laps, they go on a steep rise and I assume that we just went on a much steeper rise and increase in pressures.
"They (Red Bull) must be able to keep their pressures lower than ours and that's why ours were blistering. That was just a theory that I had," Hamilton added.
"I wasn't saying that they have different settings to us, because we all have the same minimum."
Given that Red Bull managed to win despite the fact that the Mercedes is clearly a quicker car, Dr Helmut Marko said Sunday gave the energy drink owned team hope.
"There is still a lot to come from us," he said. "The world championship is not over for us yet."
Even Toto Wolff, Mercedes' team boss, agrees with that.
"Red Bull is a title opponent for us," he said. "It will be anything but a leisurely stroll.
"Without the retirement at the first race, Max would be much closer to Lewis now," Wolff added.
"Yes we have the fastest package, but it is not the fastest under all circumstances. That is why we have to learn how to tune our car so that the tyres do not suffer like that."
As for whether Verstappen can repeat his winning feat this weekend in Barcelona, however, Hamilton is not so sure.
"I expect it to be similar to the first Silverstone race," said the championship leader. "The tyres will be at the limit, but not quite as bad as in this race."
