The Mercedes pit wall saw the debris that Valtteri Bottas struck in the Azerbaijan Grand Prix half a second before the impact.
Bottas looked set for victory in the Baku race before he suffered a puncture to his right rear tyre after he hit debris following the final restart.
The FIA said it had not seen the debris Bottas hit, and while Mercedes revealed it did spot it, the team admitted it was too late to do anything about it.
Mercedes trackside engineering director Andrew Shovlin said that the team had constantly been telling its drivers to look out for debris after earlier incidents.
"We didn't give him warning, because we didn't see it," Shovlin explained in a Mercedes video. "The first time we saw it was just as he came over those bumps.
"That was why he was also blind-sighted. You could see him heading towards it, but it was half a second or a second or so, and it was not enough time for us to get on the radio and tell him that there was debris on the track.
"If we had seen it we would have warned him, as we were doing a lot of the other laps with the other accidents. We were trying to guide them as to the best bit of track to avoid it. Unfortunately on this occasion it was all too late.
"It was a real shame for Valtteri, he'd driven brilliantly all weekend, a super composed race."
Shovlin said that the team had been banking on a late safety car when it left Bottas out after leader Sebastian Vettel pitted, knowing that there was a chance that he would be able to stop and stay in front.
"Absolutely, that was what we were hoping for. It's Baku, and there's a pretty good chance of getting a safety car. When Sebastian came in he leaves this window so that he's sufficiently far behind us so that if we stop under a safety car or a VSC, and you get the shorter pit loss, we could actually take the lead of the race.
"They're hoping that there isn't one, but it's one of those strategies that you play for. It's actually quite difficult to leave the race and control it, because you are protecting against people undercutting you, but also this issue with the safety car, and you can't do both. So that's where it does create opportunities for whoever's in P2."
The alternative plan was to give Bottas a late stop under green for the quicker ultra soft tyre, which would have allowed him to sprint to the flag – and catch up with leader Vettel in a repeat of Bahrain.
"If there hadn't been a safety car, we would have come in with Valtteri, we would have taken the ultrasoft, about 10 laps from the end of the race. The super wasn't degrading, it was going really well, and we could run it as long as we liked.
"Those 10 laps would have given him just enough time to catch up with Seb, and battle him for the win. And he would have done that with a couple of laps remaining."