The 19-year-old was brought off at half-time, with Jurgen Klopp explaining that it was due to his midfielder picking up a yellow card, which came after bringing Pereira down.
It was a late, two-footed challenge in which he missed the ball and collided nastily with the Leicester full-back, but referee Andy Madley only saw fit to book Morton.
Pereira played on for another half-hour, but it has now been revealed that he fractured his fibula, with Brendan Rodgers expecting him out for six to eight weeks.
That it came in his first game in six weeks, following a hamstring injury, added to his and Rodgers’ frustration, but taking to Instagram to reflect, Pereira claimed he is “lucky” his season isn’t over:
“Perspectives. You can say I should feel unlucky after coming off in my returning game and part of me is,” he wrote.
“But after what could be a season-ending tackle, what could be an ACL, I’m feeling lucky it’s none of those even though I’ll be out some time.”
He added, with a shrugging emoji: “Like I say, it’s perspective, for some it was just a yellow card.”
Morton was fortunate to not be given his marching orders, and the hope will be that he learns from this and takes it with him as he develops in the side.
“He has obviously learned and listened to a lot of the lads around him in training and being around the lads, in the dressing room and in training, it will certainly help him,” the captain said.
“And I think that has helped him going into games, I think he has looked comfortable and he hasn’t looked fazed at all and he has done really well.
“So hopefully he can just carry on doing that.
“He is a great lad as well, he has worked extremely hard and I’m sure he’ll have a big future ahead of him.”