Truro boss Lee Hodges says his side were 'flat' as they lost 3-0 at home to Conference South leaders Welling.
"We never really got that ball down and played at the tempo we asked them to do," Hodges told BBC Radio Cornwall.
"It was a strange type of game. We were 2-0 down at half-time and they'd had two shots on goal.
"We hit the inside of the post and had a couple of half-chance headers at set-pieces. We never really got going and it just seemed flat."
Former Plymouth Argyle midfielder Jordan Copp made his debut for City after joining on Friday and impressed Hodges with his first performance.
"He was the livewire that we wanted," said Hodges.
"When he had the ball he looked lovely and did ever so well on his debut."
Bottom side Truro are 17 points from safety with eight games to go, but Hodges says they have to remain positive.
"There is a fighting sprit in there - we have to pick up as many points as we can from now until the end of the season," he insisted.
"If we feel sorry for ourselves we'll get beaten in every single game.
"They have to be mentally strong enough to go out there and perform and compete against teams like Welling, who look like they're going into the Conference.
"If they decide that they don't want to be out there and just go through the motions they won't be in the team."