Brentford 0 Notts County 1
Jon Stead proved an FA Cup hero in west London for the second time in three years as a much-changed Brentford were dumped out by the League Two high-flyers.
Stead, part of the Bradford team who stunned Chelsea in the fourth round in 2015, curled in a brilliant shot from the edge of the box midway through the second half to settle this tie.
The Bees were frustrated by fine saves from County goalkeeper Ross Fitzsimons, some committed defending and a remarkable goal-line clearance shortly before Stead’s winner.
Alan Judge returned after 21 months out through injury but it was almost debutant Emiliano Marcondes who rescued a replay as his injury-time header hit the post.
Boss Dean Smith retained only three of the team which lost at Wolves on Tuesday and there was too often a lack of cohesion as a result.
It took the Bees 25 minutes to threaten as Florian Jozefzoon forced a good save from Fitzsimons, who later turned away a Neal Maupay effort.
Then came the major turning point. Ollie Watkins, who had only just come on, pounced on a blocked shot and it appeared to be heading in, only for the ball to spin away and be cleared off the line by Shaun Brisley.
County went up the other end and Stead – who scored one and made two in Bradford’s victory at Stamford Bridge – found the far corner.
Fitzsimons then pushed behind a Jozefzoon effort and County continued to block crosses and shots as the Bees pressed late on.
They could have made the closing stages less tense when Jorge Grant broke clear but Luke Daniels made a good save.
Brentford: Daniels; Clarke, Mepham, Barbet, Chatzitheodoridis (Canos 77); Macleod (Judge 70), McEachran, Mokotjo (Watkins 63); Marcondes, Maupay, Jozefzoon.
Subs not used: Balcombe, Yennaris, Sorensen, Sawyers.