Fleetwood knocked out in-form FA Cup Sheffield Wednesday to reach the fifth round for the first time.
Carlos Mendes Gomes headed the only goal to decide the fourth-round replay and arrange a trip to Burnley.
Darren Moore’s Wednesday side top League One and have been unbeaten in 15 games since early November.
Fleetwood has lost four consecutive games in the same division, and it was their first victory against Wednesday in the sixth time.
With half an eye on Saturday’s trip to Ipswich, Moore made 10 changes from the side that beat Plymouth on Saturday, including making a debut for 17-year-old Sean Fusire.
Fleetwood headed the early stages and the lively Promise Omochere – who scored in the 1-1 draw at Hillsborough in the initial draw – headed a first chance wide and moments later spun into the box and hit a shot against the post with David Stockdale flat-footed.
The pressure continued as Omochere headed for another wide chance and fired off target after another rotation.
Fisayo Dele-Bashiru fired straight at Jay Lynch at the other end after a neat shot from Lee Gregory who then rocked the underside of the crossbar with a header just before the half hour mark.
Phoenix Patterson curled in narrowly and Danny Andrew drove straight into Stockdale before the break, but the hosts couldn’t find a breakthrough despite all their dominance.
After a series of changes from Owls at the break, Fleetwood had to wait until the hour mark to break the deadlock as Mendes Gomes rose the highest to power a header from a free-kick past Stockdale.
Cian Hayes saw penalty appeals dismissed soon after, but it was Moore’s side who finished stronger.
Michael Smith saw a deflected shot wide, Dele-Bashiru saw penalty appeals dismissed, while Smith hindered an effort from Mallik Wilks and George Byers fired wide as the visitors trailed off.
Fleetwood’s fifth round match at Turf Moor will take place on Tuesday February 28 or Wednesday March 1.
Sheffield Wednesday boss Darren Moore told BBC Radio Sheffield:
“I said at half-time that I wasn’t happy with the way we started the game. We were lackluster in our approach and they were more on the front foot. We had a few scares in goal and (David Stockdale) made one or two saves.
“In the second half we came into the game more, we had a couple of half chances that I thought we could have done better with. Losing the game the way we did, on set play , is really disappointing because it is something from this season that we are very proud of.
“The result tonight – we have only ourselves to blame.”