Nottingham Forest were frustrated by an organised Preston North End display in a goalless first half of their FA Cup fourth-round tie at the City Ground.
The Championship outfit, two-time winners of the competition, had two early efforts on the visiting net but have since found it difficult to break down Preston's compact defence.
Jamie Paterson, who scored a hat-trick in the 5-0 thrashing of West Ham United in the last round, saw a long-range shot fly narrowly wide of the post, while Simon Cox tried his luck from a tight angle and forced North End stopper Declan Rudd to parry behind on nine minutes.
Greg Halford's unthreatening header from the resultant corner was the last time Forest converted their dominance in possession into a noteworthy chance until Jamie Mackie came close on 38 minutes.
After good work from Gonzalo Jara on the right wing, the former Queens Park Rangers striker thrashed a shot just off target as Forest failed to take a half-time lead for the first time in five home matches.