Lando Norris said the three-place grid penalty he was given at the Azerbaijan Grand Prix was "unfair".
The McLaren driver was penalised for failing to pit immediately after one of four red flags during qualifying.
The usual five-place penalty was reduced because Norris "had only a very short time to react," stewards said.
"A bit gutted," Norris said. "I didn't feel like I did anything wrong. I felt [it] was the safest thing to do. It's a bad decision or an unfair penalty."
The decision drops Norris from sixth on the grid for Sunday's race to ninth.
McLaren team principal Andreas Seidl said Norris had just one second to decide on his course of action when the red flag was shown following a crash by Alfa Romeo's Antonio Giovinazzi as the Briton approached the pit lane entry.
The stewards' report said: "The driver admitted that he lifted the throttle, braked and was committed to and able to enter the pit lane.
"At that moment he was not sure what to do and asked his team over the radio.
"Although the team ordered him immediately to enter the pits, it was too late and Norris crossed the finish line one more time.
"The Stewards assume that if a red flag is not respected during qualifying, a drop of five grid positions is appropriate. However, if you consider that the driver only had a very short time to react due to his position on the track, a drop of three grid positions is sufficient as an exception."
Article 31.6 of the F1 sporting regulations states that when a red flag is shown to stop the session "all cars must immediately reduce speed and proceed slowly back to the pit lane".
Norris said: "It sucks because I guess there's a rule [but] also sometimes there's some more leniency to certain situations when the driver's still done the best thing that's possible to do in that situation."
Norris was also given three penalty points on his licence, taking him to eight. Twelve points in one calendar year means an automatic one-race ban.
Norris said: "For all I knew, the pit lane could have been blocked and you're not allowed to enter the pit lane and then it could have been a different story, like: 'Why did you enter the pit lane? You shouldn't have done that.' So it's a tough one.
"I didn't put anyone in harm's way. If anything, I took the safer option out of boxing [pitting] and not boxing and that makes it even worse. So I don't deserve three points on my licence for this, I didn't do anything dangerous."
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