Lewis Hamilton was left "very confused" by the FIA's mid-race change of stance on track limits at Bahrain's Turn 4, a decision that also baffled rival Max Verstappen.
The Red Bull driver had seized the lead from Hamilton in the closing stages of the Bahrain GP but only after running wide on the exit of Turn 4, a move that was frowned upon by the stewards who ordered the Red Bull driver to give back the position to the Mercedes driver.
Verstappen duly executed the order but lost the race in the process. Hamilton welcomed the decision but nevertheless questioned why there had been a mid-race change in policing the corner when it had been clear from the outset that drivers would not be sanctioned in the race for running wide.
"I think it is very confusing," said Hamilton. "At most tracks we’re not allowed to put four wheels outside the white line, but this weekend and at that particular corner, we weren’t allowed to on Friday.
"In actual fact, you could go two wheels outside the line, but you can’t go past the blue and white kerb. But in the race you can, and that was what had been written.
"So when we go into the race, then you can. But it’s quite a different corner when you have to do one or the other in terms of approach. And it is faster when you can go out."
Video evidence indicated that Hamilton had ran wide at Turn 4 on 29 consecutive laps without being given the slightest warning, a practice that wasn't lost on the Red Bull team who eventually encouraged Verstappen to do the same.
But out of the blue, the Mercedes camp was informed by race control that Hamilton's track limits abuses were no longer acceptable.
"Halfway through the race they basically changed their minds and all of a sudden you’re not allowed to go outside that white line," said Hamilton.
"Which is fine for me, it’s actually I think faster in the end for me, and helped me look after my tyres, actually. So I’m grateful for the call."
Verstappen was equally confused by the sudden change of stance on Turn 4.
"Throughout the race I was told that people were going wide, so they told me to do the same because you do gain lap time doing it," explained the Dutchman. "So I did. And at one point they told me not to do it any more. So I don’t know.
"In qualifying, of course, it was not allowed, your lap time got deleted. And so I don’t know how it got to the point where people were doing it without getting warnings.
"But at the end of the day when I was fighting Lewis, I went outside of the track limits. I think quite quickly the race director was onto us to tell me to give the position back, so that’s exactly what I did."
Both Red Bull and Mercedes team bosses were unhappy with the lack of clarity regarding the enforcement of track limits in Bahrain.
Christian Horner reckoned that Hamilton gained a two-tenth advantage each time he ran wide, until he was told to remain within the track limits, while Toto Wolff sought clarity from the FIA on track limit rules, insisting that drivers required clear and consistent directives.
"So we need to be consistent in which messages are being given," argued the Austrian. "They need to be clear, they need to be sacred and not a Shakespeare novel that leaves interpretation."
Wolff revealed that he and Mercedes sporting director Ron Meadows were in contact with FIA race director Michael Masi during the race, seeking clarity on the exact rule that applied to Turn 4.
"The message that reached the drivers was that very simply track limits in Turn 4 wouldn't be sanctioned in the race," Wolff said.
"Ron and I were speaking to Michael [Masi] during the race. Michael referred to the note saying 'Yes, but only if you're not gaining an advantage' and that was in the notes. I haven't seen them.
"I think the learning of this is it needs to be simple, so everybody can understand it and they don't need to carry the document in the car to read it and remind themselves what actually is allowed and what not."