Lewis Hamilton has accused Sergio Perez and other drivers of not strictly following the rules during qualifying for the Spanish Grand Prix.
The Briton will line up in sixth on the grid for the event, with the Red Bull of Perez ahead of him in fifth.
Hamilton admits that he was pleased to see the progress that Mercedes have made during the weekend so far, but was left feeling disappointed by others around him allegedly not sticking to the guidance set out in the Race Director's Event Notes.
Hamilton unhappy with Perez and others
"I'm disappointed with the result, because we've definitely moved forward, which is great," Hamilton explained after qualifying.
"On one side, there's a rule that we have to stick to a delta time. With these tyres, if you do a really slow out lap, you can save so much temperature, and you gain a lot of time through the lap.
"There were several cars ahead of me who didn't stick to the delta. You've got Perez, for example, who is eight seconds slower than the delta time you're supposed to allow.
"That's like five degrees of temperature, and that's an advantage that he's carried into the lap.
"I stuck to the delta, so that's a bit frustrating."
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Frustrations for Hamilton
Hamilton will line up behind teammate George Russell, who put his Mercedes in P4 on the grid.
The seven-time World Champion remains happy with the job that the team have done to get to this point, though.
"The car clearly has better performance," Hamilton said.
"George was slower also on the out lap, so I think he probably got a bit of an advantage with that. But, nonetheless, we've done a really good job to be where we are.
"I'm just in the same position that I am always [in], so that's the frustrating thing."
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