Sunderland Under-23s manager Elliott Dickman believes his side need to be nastier following their 3-1 defeat by Middlesbrough on Monday night.
The Young Black Cats lost 3-1 at Eppleton CW, Hetton, despite taking a first-half lead through Jake Hackett.
Boro scored three times in ten minutes after the break, condemning Dickman's side to their ninth league defeat of the season.
But the Sunderland boss doesn't believe the result reflected the team's performance.
"I was really pleased with the first half, I think we did ok, what I could see anyway with the fog," said Dickman after the game.
"I thought we were competitive, I thought we made the game difficult for them and we were well in the game.
"To be honest I didn't see it coming, them scoring, and once they did score we've let ourselves down again."
Duncan Watmore played just under an hour for the hosts as the striker continues to step up his recovery from a serious knee injury.
Sunderland also handed a start to trialist Sam Smart, who won a penalty in the first half before he was replaced after the break.
At the same time, Boro brought on Gabby McGill for Kian Spence when Sunderland were 1-0 up, and Dickman believes the substitutions altered the game.
"The next two goals were a bit too easy for them but substitutions change games," added Dickman.
"They've made one which I thought affected the game more than the ones that we made.
"The majority of the lads have worked hard and it's good for them to play in a tough game."
Sunderland remain bottom of Premier League 2, Division 2, with just four points from 11 games, and have now lost their last six league fixtures.
And Dickman admitted his side need to develop a nastier edge which will allow his side to close games out.
"The lads know how disappointing it is to concede like that," said Dickman.
"Even before I've gone into the changing room I can hear them having a go at each other, that's quite encouraging that they're aware of it - but they have to actually do it when they're out on the pitch.
"They have to make sure when they're out there they make it harder and make it difficult, exactly what they did first half.
"They just have to keep their concentration, keep their focus and at times they have to be a bit nastier, especially when they're defending.
"There's lots of positives within the game but there are bits we need to improve upon which we'll get back on the training ground and definitely work on."