Having started from the pitlane, Gasly collected a piece of advertising hoarding that flew off a barrier when Sainz crashed on the first lap, and was forced to pit for a new nose.
A red flag then came out, and Gasly – running on his own – was shocked when he passed close to a tractor that had ventured out on track.
The incident was not shown on TV at the time, but a video of it quickly spread on social media.
Having viewed it during the red flag break Norris was quick to take to Twitter, referencing Jules Bianchi's 2014 crash.
He wrote: "Wtf. How’s this happened!? We lost a life in this situation years ago. We risk our lives, especially in conditions like this. We wanna race. But this… Unacceptable.”
Having been shown the video by Autosport, Sainz echoed those sentiments.
“What people don't understand is that even behind the safety car going 100, 150kph, we don't see anything,” said the Spaniard.
“So even if there's a crane on track and we are behind the safety car going 100kph, one driver could do a small mistake, a stupid mistake, go a bit offline, not remember that there's a tractor there, and crash into a tractor. So why even risk it? I guess this is more our point.”
Sergio Perez also agreed that the incident was "unacceptable."
The Red Bull driver tweeted: "How can we make it clear that we never want to see a crane on track?
"We lost Jules because of that mistake.
"What happened today is totally unacceptable!!!!!
"I hope this is the last time ever I see a crane on track!"
When Autosport suggested that Gasly might be blamed by the FIA for going too fast Sainz said: “I think you don't need to leave it to the luck of the driver. I think you are going to red flag the race anyway, why send a vehicle out?
“Maybe wait a bit to bunch the field up, I don't know, and go really slow. The driver is always going to in an extreme, try to put a bit of temperature in, in case the race gets restarted. It's a tricky one, but yeah, quite risky.”
Asked about his own accident Sainz admitted that having spun to a halt he was terrified about being hit by another car.
“I had zero visibility already in fourth and trying to get out of the spray I went into a puddle on an intermediate tyre. That doesn't evacuate as much water, and I went into a spin.
"The worst part probably came later when I was in the middle of the track, spun, and I knew that everyone behind me was not going to see if I was there or not.
“Not ideal for sure. There was 20 seconds where I didn't know if I was going to get crashed, bracing and just expecting and hoping that my mates were either going to have good reflexes or good luck."
Asked if the race should have been started he said: "Laps to grid, there was very poor visibility but the track was in good conditions for inters and for doing the race.
"But very poor visibility probably even for a race start. I talked to a few drivers who were starting 11th, 12th, around that area and they were saying they knew they were going to see nothing at the start.
“We saw that it kept raining at the race start so we were all looking at each other like we're all going to be on inters and there's going to be zero visibility, and probably more complaining.”