Eric Kinder was bitterly disappointed with how the Under-21s performed on Monday night as they fell to a 2-0 home defeat to Middlesbrough.
The visitors were the stronger of the two sides throughout, with two fantastic strikes settling the match. Andre Bennett opening the scoring in the first half before Emmanuel Ledesma's emphatic finish in the second.
Jordan Slew had a goal disallowed whilst substitute Connor Mahoney had strong claims for a penalty waved away towards the end, but they were rare opportunities as the development squad ended their 2013 campaign in disappointing fashion.
"I think it probably should have been more," Kinder told Rovers Player. "We are very disappointed tonight. It was not the performance we were after coming off the back of the Manchester United game.
"We don't take enough care in possession, we don't take enough care in the things that we do and we are going to have to learn pretty quick.
"They seemed to have a lot more enthusiasm, especially in the first half, and they had more desire. It is unacceptable saying things like that.
"If they are better footballers and we compete with them then we can't argue, but we didn't compete with them, especially in the first half.
"The second half was a little bit better but the first half was unacceptable.
"I just said in the dressing room that there are a lot of people in there fighting for contracts and that isn't the way to go about it.
"You've got to be better than that, we've got to be better than that all round."
One of the few bright spots on an otherwise miserable evening at Leigh Sports Village was the substitute appearance of Connor Mahoney.
The 16-year-old, signed last week from Accrington Stanley, had a lively 20 minutes on his Rovers debut, with the Under-21s boss encouraged by what he saw.
Kinder added: "I'm struggling to find any positives, but probably at the end when the young lad Connor Mahoney comes on he shows a glimpse of what he is going to be capable of when he gets a little bit older.
"It was always our intention to get him on tonight and get a quick look at him, he's only been with us a couple of days but we saw a couple of glimpses there to think that we've got a lot to work with.
"He was very nervous before he went on, he's making his debut for his home town club and he's desperate to do well.
"I was pleased with him, there is plenty to work with."