MONACO -- Almost as surprising as seeing a Ferrari on pole position in Monaco was seeing how much championship leader Lewis Hamilton struggled.
The Mercedes driver will start Sunday's race from seventh on the grid after qualifying 0.749s off Charles Leclerc's pole position time on Saturday.
It is the first time Hamilton has qualified outside the top two this year and is his worst qualifying position since he suffered a hydraulic failure during qualifying at the 2018 German Grand Prix and started from the back of the grid.
Asked what went wrong, Hamilton said he struggled to get his tyres in the right temperature window to maximise their performance.
"Today was a question of tyres, the tyres just not working -- sliding around," he said.
"There will be some tough discussions that I'll have with my engineers, tonight or maybe after the weekend, as there are things that should have been done which haven't been done.
"We'll learn from it and come together stronger in the race."
Asked to expand on what went wrong, Hamilton added: "I can't really no.
"But as I said, from my point of view it's a little frustrating, but it is what it is.
"I can't really say too much about it. At the end of the day, this is a team.
"Also, I don't' want to be critical of team, but behind closed doors, I will be. We've got to work harder."
Hamilton said his Mercedes team took the wrong setup direction after Thursday practice and made the car worse in final practice ahead of qualifying.
"We made lots of changes to the car after FP3, as FP3 was a disaster, and that was from the work done over the last day or so.
"Completely wrong direction. Completely missed the ball.
"Then we made some changes to try and take steps backwards and move the car into a different place and the car was worse than ever.
"We really lost our way on Thursday."
Team principal Toto Wolff said the post-qualifying debrief with Hamilton had been "tough" and "brutally honest".
"We just had a very productive and tough debriefing and this is exactly the days when we learn the most," Wolff said.
"This team has a brutal honesty and transparency within itself and we didn't get things right. It's not completely clear yet how all the tuning possibilities were interacting with each other, but I would say we were not having enough grip in each of those runs and probably linked to tyre temperature.
"Again, we need to analyse that, but one thing is for sure, we were not competitive. We did not provide Lewis with the right car to build up the confidence and based on a good gripping car that he would like to have.
Wolff admitted the team pursued a setup direction against the advice of Hamilton.
"There was one particular aspect of tyre heating we discussed this morning and on Thursday night where we could have taken a different direction and a direction he was interested to pursue but didn't," Wolff said.
"That was exactly the content of our discussions now [in the debrief]."
Wolff said he had no issue with Hamilton blaming the team after things went wrong.
"We want the drivers to speak their mind and there was a lot of frustration," he said. "When you are finishing qualifying in P7 in Monaco you know pretty much that is the end of the weekend.
"Venting your frustration is absolutely OK, and no one in the team takes it the hard way because we express it the other way around too.
"He is the first to acknowledge and apologise when things go wrong, he has done it publically and privately, but as a group that is one of our big assets that made us champions in the past -- we can take it on the chin."