Romelu Lukaku had an afternoon to forget at Old Trafford on Sunday.The Manchester United striker not only missed a big chance to equalise late in the second half but also inadvertently set up both of Manchester City’s goals.It was his accidental knock-down from a City corner that led to David Silva’s opener. He then horribly messed up a clearance early in the second half and Nicolas Otamendi duly capitalised with a close-range finish.United fans on social media were understandably furious with the Belgium international (click HERE to see some of their tweets).He then spurned a glorious chance to make amends; denied by an excellent save by City’s goalkeeper Ederson.The Daily Mail - and other publications - handed Lukaku the lowest rating (4/10) of any player on the pitch for his disappointing performance.

Alan Shearer dropped truth bomb about Lukaku on MOTD 2

On Match of the Day 2, meanwhile, Alan Shearer didn’t hold back.

The Premier League’s all-time leading goalscorer dropped a truth bomb about Lukaku, claiming United’s £75 million striker isn’t doing enough in games to justify his huge transfer fee.

“No one was asking these questions earlier on in the season when Lukaku was scoring 11 goals in his first 10 games,” Shearer told BBC's Match of the Day 2, per the Daily Mail.

“No one was asking the question of Mourinho then and whether he had improved Lukaku. He's not doing enough in games - and I hate saying it - to justify his fee.

“He looks to be lacking in confidence, two in 13 now but in his defence with some of the balls and some of the service he was feeding on scraps. Everything seems a second or two too slow and by the time he's made his mind up it's gone.

“From a centre forward's point of view that's what makes the difference between the very good strikers and the good strikers. You get one chance like that and it has to be in the back of the net.

“His mindset now - I know mine - if i'd missed a chance like that I wouldn't sleep for the next three or four days until the next game or until i'd scored again. That missed chance would be on my mind until then.”

Video: Shearer's Lukaku rant

You can watch Shearer's rant (minus the match highlights) here...

Twitter reaction to Shearer's rant

Lukaku has scored 13 goals in 24 matches since joining the Red Devils from Everton in the summer but has flattered to deceive since his magnificent start during the first two months of the 2017-18 campaign.

Here’s what Twitter said about Shearer’s Lukaku rant…

Is Alan Shearer right about Romelu Lukaku? Have your say by leaving a comment below.