Burton manager Nigel Clough is relishing the prospect of a last-16 tie against Leicester after coming within two minutes of facing a third-round replay with Bournemouth due to floodlight problems.

Goals from Oliver Sarkic and Nathan Broadhead resulted in last season’s semi-finalists causing a stunning upset in dispatching Eddie Howe’s in-form Premier League side. But three second-half floodlight failures at the Pirelli Stadium, caused by issues within the local area and not with the ground’s own system, resulted in 28 minutes of delays.

Referee John Busby even called a halt to proceedings after the third failure, only to be told by the Football League a match can only be called off if there is a total delay of at least 30 minutes.

Clough said: “I’ve never experienced anything like that, not going ‘on off, on off’ for floodlight failures. But it was a problem no one could control. I’m just delighted to get the game finished, and Bournemouth were desperate to get it on as well. They didn’t want to come back in a couple of weeks’ time.

“But initially we got conflicting messages. It was the Football League who said you have to give it 30 minutes in total for outages. No matter how many times you stop, if it’s not 30 minutes … and we were still within that, and that’s why we went back out that final time.”

Nathan Broadhead celebrates scoring Burton Albion’s second goal. Photograph: Craig Brough/Action Images via Reuters

Sheffield United coach Chris Wilder admitted his fringe players were second best against Sunderland after they were knocked out by the League One side. Max Power’s superb 25-yard strike after nine minutes gave the Black Cats a 1-0 win at Bramall Lane and it was the visitors who came closest to scoring the game’s second goal when Luke O’Nien’s shot struck a post in the second half.

“We didn’t do enough and we didn’t deserve to go through, we were second best,” said Wilder. “There would have been a time when I’d have had them in the dressing room dissecting that until 11.30pm but we’ve got the European champions coming here at Saturday lunchtime and I’m not going to waste my time on it.

“It was an opportunity for some players to knock on my door and ask why they aren’t in the team, well I don’t think there will be any knocks on my door, apart from maybe Mo Besic. And I thought the two strikers who came on did okay. I made 10 changes and Sunderland made eight changes and their changes were better than mine. They were pretty comfortable in the end and saw the game out comfortably.”

Wolves head coach Nuno Espírito Santo expressed his concern after debutants Bruno Jordão and Meritan Shabani were both carried off in their penalty shootout win against Reading.

Jordão has an ankle injury after a challenge with Charlie Adam and Shabani’s is a mystery after he buckled, unable to straighten his leg with no one around him as Wolves advanced 4-2 on spot kicks after the tie ended 1-1.

“Shabani looks like a long one, he is now being analysed by the doctor, then we will know what happened but it looks bad. We don’t know yet,” said Nuno. “Jordao’s is a different situation – someone fell on him and he twisted his ankle.”

Brighton manager Graham Potter says injuries and sickness forced him to field a youthful side for the third round loss to Aston Villa.

Potter named a starting XI with an average age of just over 21 and handed 10 senior debuts to academy players during the course of the 3-1 defeat at the Amex Stadium.