Alpine had its best qualifying result of the season in the principality, with Gasly and Ocon qualifying 10th and 11th respectively on a track where overtaking is notoriously difficult.
Carlos Sainz's puncture at the start promoted the blue-and-pink cars to ninth and 10th, but Ocon went on to dive down the inside of his team-mate at Portier, with their wheels interlocking.
Ocon was launched into the air and had to retire due to the resulting suspension and gearbox damage when his car landed heavily on the ground.
Meanwhile, Gasly was able to keep racing despite a punctured hard tyre, with the red flag coming in handy to get new medium rubber he had to nurse to the finish. He scored his first point of the season in a very uneventful race.
Albeit relieved to end his points drought in a context where "a point or two might be crucial at the end of the year", Gasly admitted he "was quite shocked" by the contact with his compatriot.
"It was very unnecessary; you should never have such a situation, especially between team-mates," the Frenchman said.
"Just sad. Disappointed with the situation.
"Especially, we had clear instructions before the race on what to do, and whoever qualified ahead, the trailing car was supposed to help throughout the race.
"That was the strategy. Unfortunately, it didn't happen.
"We definitely need to speak because we can't afford [it] – especially in a season like that."
Gasly insisted that Ocon jeopardised what could have been an even better result for Alpine: "At that time, we're P9 and P10, so there's absolutely no reason to risk to get both cars out.
"We came a couple of centimetres from having both cars in the wall."
Asked whether Ocon's aggressiveness was inevitable, with him keen to secure an F1 seat for 2025, Gasly retorted: "I don't want to answer that, [he's] a professional driver.
"You just know what do to and what not to do – even more with your team-mate.
"He's a very good driver, he knows what he does, so he just needs to make a change."
Meanwhile, Ocon took to Twitter to shoulder the responsibility of the incident, which the stewards gave him a five-place grid penalty for ahead of the Canadian Grand Prix.
"Today’s incident was my fault, the gap was too small in the end and I apologise to the team on this one," he wrote during the race. "Hoping for a deserved points-finish for the team today."
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