Former Liverpool manager Graeme Souness believes that Manchester United may end up regretting their decision to let Romelu Lukaku depart.
The Belgium international arrived at Old Trafford from Everton in the summer of 2017 and scored 42 goals in 96 games for the club before heading for Inter Milan two years later.
Lukaku has since re-signed for Chelsea in a £97.5m deal and has made quite the impact during his first few weeks at the club, bagging three goals in three Premier League games.
Amid the striker's good fortunes in front of goal, Souness believes that United may look back with disdain on the decision to sell him, saying: "I don't think Manchester United should've ever let him go," in quotes attributed to The Mirror.
"He seemed unhappy when he was there, and he's come back a happy man. He definitely is a key man. Goals change games. If you have someone who can nick goals then all of a sudden you're a different team.
"He hasn't got a weakness. I'm not saying he's brilliant at everything but he's got no obvious weakness. If you're playing against him and you're a centre-back you're not going to enjoy it.
"I don't think anyone will enjoy playing against him, he's got a bit of everything in his game and he'll be the difference for them should he stay fit."
Lukaku notched up two of Chelsea's three goals in Saturday's 3-0 success over Aston Villa.
