Portsmouth extended their winless League One run to nine matches after being held to a draw by Preston.
Pompey striker Izale McLeod earned his side a penalty but stepped up to blaze a fierce effort against the crossbar.
Preston nearly snatched the lead in the final minute of the first half but Joel Byrom's effort was well saved by Pompey keeper Simon Eastwood.
Scott Allan had Portsmouth's best attempt of the second half, but his powerful effort was tipped over.
The result leaves Pompey in the relegation zone and one point from safety.
VIEWS FROM THE DRESSING ROOM
Portsmouth caretaker manager Guy Whittingham told BBC Radio Solent:
"We had enough chances, enough pressure, and the way we played I thought was pretty positive. All that was missing from that performance was a goal.
"If we'd taken it [the penalty] then obviously it would have been a 1-0 victory and that would have been great, but it isn't and I don't think we ever reflected on that. We kept pushing forward and kept looking for the goal.
"The pleasing thing is that we haven't conceded. We needed to make sure we tightened up at Fratton Park because we have conceded far too many goals here."
Preston North End manager Graham Westley told BBC Radio Lancashire:
"It's never going to be an easy place to come to, whatever situation their club is in.
"I thought it was a hardworking performance from us. We made a number of changes to the side and it was always going to be difficult for the lads to show genuine organisation.
"On the whole, they worked hard to stay solid and come away with the clean sheet.
"It was a solid away performance, if unspectacular."