That appears to have angered Koeman, who says it is unfair to single out individuals for their performances in the defeat.
Everton will go to Old Trafford with the same young squad as they took to Anfield on Saturday and Koeman, who plans to visit Seamus Coleman in Ireland next week as he recovers from his horrific leg break, has stood by the comments he made about being proud of the performance against Liverpool. I don't understand some comments, but I understand others.
"Maybe some players did not perform at the level they have shown in the last few games", he said. With Romelu, it was hard. I spoke to Romelu, he was not really sharp, he was a little bit exhausted. He wasn't really sharp, he was exhausted and that can influence the performance of a player.
Pat Nevin believes it wouldn't be the worst idea for Everton to cash in on Premier League top scorer Romelu Lukaku and sign two to three players to improve the team.
"Obviously its still raw that we lost against Liverpool and we are very disappointed but the best thing we can do now is get our heads right on Tuesday and make sure we get the three points there".
"He's a great striker. That's football. If you don't play football, maybe you don't understand". That's why it's a derby, and the second edition of the Merseyside derby (won by Liverpool 3-1) this year was just as heated as you would expect.
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 a little bit of a different position to that which he played in the last few weeks".
"But not to take out one or two and [say] that was the problem last Saturday, no that's not fair".
"It's easy to pick 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.
"To compete against a strong team is always hard but what I try to be is realistic about the situation, the team, the progress it is making and the project at Everton".
United, who are fifth in the table, have drawn eight of their 15 home games in the league this season, and Koeman urged his team to try and impose themselves on the contest from the outset.