Toto Wolff admitted that Lewis Hamilton's qualifying session in Monaco almost came undone because a set-up decision they made on Saturday ended up not working out.
"The team - with Lewis - decided to take a bold decision with the set-up because we thought we could play at the front, but that backfired," the Mercedes principal told the media afterwards.
"We felt it was important to compromise grip in the first sector and then have it later on. It made the car tricky to drive in turn 1, and that was it," he said. "It put him on the back foot in qualifying; the car never felt really together.
"The recovery was very good ... there was a lot of pressure so finishing P6, three-tenths off pole. That is solid in terms of the time gap," he said, while admitting "the position is not great" in terms of what can be done at Monaco.
"We'd been trying something through the weekend, and there was some uncertainty with it," Hamilton explained in the paddock.
"Our middle sector has been where we're losing out all this weekend so far, so I made a change into qualifying, which made it harder for us in the last sector," he said. "But you can't always have your cake and eat it.
"We went back halfway on the other car [Russell's]," he explained. "But I went the full way on mine. I was like, 'We should take it off!'. And they were like, 'No, no, we should keep it, we should keep it!'
"I was certain of it and said, 'If I'm wrong then I'll put my hands up'. At the end I think it was okay. Probably for a single lap it was a little bit worse, but for the race I think it will be better."
Hamilton had already suffered a bruising end to final practice when he crashed at Mirabeau, forcing the Mercedes mechanics to work over the lunch break to get the W14 back in one piece in time for qualifying.
When he got back out on track, Hamilton seemed to be struggling for pace. He scrapped through the end of Q1 with his final flying lap, and left it late again in the second round as well.
"I struggled to get temperature into the tyres in this session so it was always that last lap that managed to just pull something out," he explained. "I didn't try to leave it late, it's just how it turned out.
"My heart was in my mouth," he admitted. "There could have been a yellow flag, it could be a red flag, who knows? But we made it through and I'm grateful for the lap that we got.
He did finally get through to the final top ten shoot-out and finished in sixth place just behind his team mate George Russell.
Both drivers had been running the latest upgrades from Brackley, with Hamilton broadly happy with the improvements he had benefitted from so far this weekend. However it hadn't been smooth sailing.
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