An inspired second-half performance from the Blades was enough to force extra time after they fell behind in the first period thanks to Brennan Johnson’s goal, but Forest goalkeeper Brice Samba saved three penalties in the shootout to send his side to Wembley.
Goals from Morgan Gibbs-White and John Fleck gave Paul Heckingbottom’s side a 2-1 win on the night, which levelled the scores at 3-3 overall.
Samba saved from Ollie Norwood, Conor Hourihane and Gibbs-White, with Sander Berge and Iliman Ndiaye converting their spot kicks.
Brennan Johnson, Steve Cook and Cafu scored for the home side, but Joe Lolley blazed his effort over the bar.
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5. John Egan - 6
Missed a good headed opportunity from close range in the opening 10 minutes. Helped keep Forest at bay for long periods of time, however. Photo: Simon Bellis
6. George Baldock - 7
Became more of an attacking threat as the game went on and produced a wonderful assist for the second goal. Photo: Simon Bellis
7. Jack Robinson - 6
In the thick of it from the off following his pre-match comments and put in a fully committed display. Used his long-throw to good effect and almost claimed an assist when John Egan connected with one after 10 minutes, but was several yards off Brennan Johnson for the opener. Photo: David Klein
8. John Fleck - 7
Struggled to get to grips in the first half but improved considerably after the break and drove his side on in search of another goal. Produced a huge moment for the second goal. Photo: Simon Bellis