Everton manager Ronald Koeman launched a fierce defence of Romelu Lukaku after the forward's performance in the Merseyside derby defeat to Liverpool was criticised.

Lukaku failed to register a single shot at goal for only the third time this season in Saturday's 3-1 defeat at Anfield, which left seventh-placed Everton eight points adrift of the Premier League's top four.

And Koeman is unhappy that the former Chelsea striker's display led to criticism from the media, who he feels do not fully understand the game.

Some former professionals also had negative reviews, with ex-Liverpool defender Jamie Carragher questioning Lukaku's record in big games, but Koeman was unimpressed to see the league's top scorer singled out.

"It is a team, every individual is part of the team and the team was not good enough, but I was proud," Koeman told reporters ahead of Tuesday's match with Manchester United at Old Trafford.

"What I don't like too much really is individual comments about the performances of the players after the game. I don't understand some comments, but I understand others.

"Maybe some players didn't perform at the level that maybe they showed in the last few games. Maybe, yes.

"Romelu, it was difficult. I spoke to Romelu, he was not really sharp, he was a little bit tired. That can all influence the performance of the player.

"But he's the top scorer of the league. Why now about the Liverpool game do we need to criticise Rom? 

"He's a great striker, he's working hard. He's a human boy, it's not always a 10, that's football and if you don't play football, maybe you don't understand it."

Ross Barkley was another Everton player to be targeted following the Liverpool loss, with much of the post-match attention focused on how he avoided a red card for a first-half foul on Dejan Lovren.

"Ross played in a little different position than he played in the last few weeks," said Koeman.

"Of course, he lost several balls in the midfield, instead of playing a little bit faster and no dribbling with the ball.

"He needs to improve on that, but not to take out one or two [players for criticism] and that was the problem last Saturday, that's not fair.

"It's easy to give your opinion in front of the television without any responsibility. I'm happy, I see a lot of progress in the club, in the team, it's a whole season, it's not one game.

"I try to be realistic about the situation of the team, its progress, and the project of Everton. It's only one game. To take conclusions is not good.

"We had six players under 22. Maybe that's something to see that, instead of expecting a Champions League team. They will learn from it."