Boss Paul Sturrock pulled no punches in summing up his sides display against Port Vale on Saturday.
Southend fell to a disappointing 3-1 defeat against the Valiants at Roots Hall.
And Sturrock admitted that the result was a reality check for his newly assembled squad.
"There should be more than frustration from the fans as there were players today that I don't believe should be taking their wages home," Sturrock told Blues Player.
"If you support a football club you expect a certain level of attitude and work rate, which I didn't see in my team today.
"Too many of these players have taken the accolades off the back of the Bristol City game and basically have let themselves down.
"Hopefully now people will be realistic and get a reality check, we are nowhere near the standard.
"We have a lot of players who are here for a reason because they have come from all different clubs of varying levels but now they are League Two players."
Blues found themselves 1-0 down after just five minutes when Justin Richards put the visitors ahead. Gareth Dodds then made it 2-0 after the break before Marc Richards added a third seven minutes from time.
United did grab a consolation goal late on but it proved too little too late for Sturrock's below par side.
"Micky Adams (Port Vale manager) has a good set of players who were well organised but it has taken him 18 months to get to that stage," he said.
"We are not going to build a team overnight, I thought we were a bit further along the line than we showed today but the potential champions of this league have beaten us.
"They played the game the way I like to see it play and I am going to work night and day to make sure that happens.
"It is not all doom and gloom because we have shown the two games prior that we can be competitive in this league but we have to learn quickly."