Carroll watched his current Olympiakos teammates inflict a damaging 2-0 defeat on his former club in the Champions League last week, and believes the current crop of United stars have been shirking responsibility since the departure of Sir Alex Ferguson.
“(The first-leg win) was a shock for a lot of press people but the players knew themselves they had a chance,” the 36-year-old said.
“We watched a lot of Premier League games this season and knew United had not been performing. On the night when I was watching it live from the stands, I’ve never seen a Manchester United team like it.
“They’ve got good players but they had no hunger, no fight in the team so it was a shock in that way but not a shock the way we played. The goals we got were well deserved.
“At the end of the day you can be a good player but you have to give 100 per cent and give everything.
“For me Manchester United didn’t give that and looked like they had no hunger and fight for the game.
“I don’t know if they thought they would get an easy game but no professional should go into a football match and think that.”
United have struggled all season under Moyes, and Carroll – who spent four years at Old Trafford between 2001 and 2005 – reckons the players have slacked off following the retirement of Sir Alex Ferguson.
“They might have slacked off since Sir Alex left, it’s football,” he added.
“People have their routines. You can’t do that in the Premier League. It’s a big league with top and bottom teams fighting for points and you have to be prepared every game.”