Truro City manager Steve Tully said he was frustrated with his side's defending in their 3-1 home defeat by promotion rivals Maidstone.
Ryan Brett levelled for the Cornish side, who conceded all three goals from long-throws at Treyew Road.
"You can't concede three soft goals like that and expect to win a football game," Tully told BBC Radio Cornwall.
"We all knew that Maidstone are a very good set-piece team and we didn't deal with that."
The result sees Truro drop to fifth, the final National League South play-off spot, two points clear of Maidenhead.
However, Tully's side have three games in hand on most of the teams around them.
"You look at the game overall and I can't fault the endeavour and the work-rate of the lads - I thought they gave everything," he added.
"We now know what we've got to do - we need seven points out of five games to finish fourth, which I believe we deserve.
"I do feel, at the moment, we seem to be playing better away from home. I don't know why that is but we do."