Stephen Dawson grabbed an injury-time winner to give Leyton Orient victory over Bristol Rovers.
David Mooney lobbed keeper Scott Bevan to put the O's ahead before winning them a penalty when he was tripped by Wayne Brown.
Ben Chorley scored from the spot but Chris Zebroski's dribble and 15-yard shot pulled one back for Rovers.
Eliot Richards pounced on a loose ball in the box to equalise but Dawson slotted home after a three-man move.
The skipper's goal earned Orient a trip to Premier League Blackburn in the third round.
VIEWS FROM THE DRESSING ROOM
Bristol Rovers manager Paul Buckle told BBC Radio Bristol:
"I'm pleased for Russell in many ways because Orient were desperate for a win.
"We started the game well but then we gifted them two goals, we know that.
"But the character was there, we didn't panic and the biggest thing for me was how we recovered. When we got the second I thought there was only one team that was going to win it."