After a goalless first half, Saidy Janko's own goal and strikes from Scott Fraser and Jake Hesketh secured the win for Burton, who were forced to hold on in injury time after substitute Arvin Appiah added to Lewis Grabban's effort to give Forest hope of forcing penalties.

Clough reached the last four with Sheffield United in 2015 when the Blades were knocked out by an 88th-minute strike from Tottenham's Christian Eriksen.

"To get to the last eight as a League One club is pretty special," Clough told Sky Sports. "We can't wait for the draw. We reached the semi-finals with Sheffield United, so it is possible. You need a bit of luck, like we had tonight."

It was a deserved win for Burton, who were playing at this stage of the competition for the first time in their history.

They could have gone ahead in the first half but Northern Ireland striker Liam Boyce sent a penalty well over the bar following a rash tackle by Liam Bridcutt on Jamie Allen. Forest also had goalkeeper Luke Steele to thank for a fine stop to deny David Templeton after he had fumbled another Boyce effort.

Burton did eventually go ahead seven minutes into the second half when Fraser's long-range effort deflected off Forest defender Janko and looped beyond Steele for an own goal. Fraser then doubled Burton's lead 12 minutes later with a smart finish from Boyce's pass.

Forest substitute Grabban converted Gil Dias' through ball to bring the visitors back into the game, only for Hesketh's fine volley to restore Burton's two-goal lead. Another Forest substitute, 17-year-old forward Appiah, scored his first goal for the club in stoppage time but could not deny Burton victory.

"If we had finished our chances in the first half the game would have been over, but it showed great character to come out and do it again," added Clough.

Forest boss Aitor Karanka apologised to the supporters after the game and said he was "embarrassed" by the performance of his side, which showed 10 changes from the team that drew with Leeds at the weekend.

"We had a chance to reach the quarter-finals for the first time in 25 years and it is a real missed opportunity," said Karanka. "If we were complacent then that should never have been the case because we were playing to reach the quarter-finals.

"I'm really angry because a team from League One, a team which has played four games in 10 days, has looked much better than us. They were much stronger and they wanted everything more than we did.

"I can't understand why that was the case and I don't want to say something that I'll regret tomorrow. I just feel embarrassed and sorry for the supporters who travelled this evening because we all came here thinking we could achieve something good."

Burton make history - the stats

• Burton Albion have won each of their lpast three League Cup games against sides from a higher division - they had lost their previous three such games.
• Nottingham Forest have lost on each of the past four occasions they have reached the fourth round of the League Cup (also 1994-95, 1998-99 and 2004-05).
• Lewis Grabban has been directly involved in 10 goals (nine goals, one assist) in his past 10 games in all competitions for Forest.