Southend United stretched their unbeaten run to 15 games by knocking League One Preston out of the FA Cup.
The Shrimpers nearly took the lead when Liam Dickinson's free-kick was fisted away by Preston's Thorsten Stuckmann.
North End responded through Paul Coutts, whose 25-yard shot was saved by Luke Daniels.
Dickinson broke the deadlock, volleying home from close range from Bilel Mohsni's header after Ryan Hall's shot was parried by Stuckmann.
Coutts had an effort ruled out for offside but the visitors could not find a way through despite a lot of pressure.
The first round replay defeat extended North End's wretched record to 12 games without a win in open play in all competitions.
And although the two teams play in different divisions, Preston sit just 10 places above Southend, whose excellent recent form has seen them rise to the top of League Two.
The Shrimpers will now host another League One side, Oldham Athletic, in the second round on 3 December.
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Southend United manager Paul Sturrock told BBC Essex:
"The first half was pretty even, it was one of those scrappy games. I told the players at half-time we just had to lift it one gear, I thought that would be enough.
"We responded properly, got the goal, I thought we got sloppy again and decided to hang on - always a dangerous concoction that. I think we just shaded it."