The Newcastle United striker was sent off for a horror tackle against Tottenham Hotspur.
The forward was shown a straight red card in his side’s 5-1 win over Spurs on Sunday, for a bad challenge on full-back Kyle Walker.
There was no denying it was deserving of a straight red, with there even being some suggestions that he should be charged further for it.
It is not the first time the Serbian has been sent off for such an offence, with five red cards already under his belt despite only being 21.
Shearer was one of those who was not impressed, saying it that he has to start learning that this sort of behaviour is not acceptable.
“He has had five red cards in his career and he is 21 years of age, the penny has not dropped and he is not learning,” he told Match of the Day.
“This challenge [on Kyle Walker] is horrific, it is a leg breaker – it is a terrible tackle and he is probably going to miss four games of next season. He has to start learning.”
It will now be interesting to see if Mitrovic remains at the club following their relegation to the Championship.
He may have endeared himself to the Newcastle faithful, but his low goal return means he has hardly been a successful signing.
There are thought to be several Magpies stars eyeing an exit after their relegation, and if Mitrovic is among them the club may consider cutting ties.