It was a competitive affair between two teams aiming to get out of the Championship come the end of the season and it was decided in the 69th minute when Lewis Grabban got his 10th goal in 11 games, deftly heading Joao Carvalho’s cross into the back of the net.
The opening 20 minutes of the game were a quiet affair as both teams tried to settle into the tie.
Oliver Norwood and Paul Coutts were both unsuccessful from distance for Sheffield United whilst at the other end, Joe Lolley smashed over a half-volley from the left of the area.
In the 25th minute, it looked like the in-form Lewis Grabban may have had an opportunity one-on-one after a fine pass over the top by Joao Carvalho but United keeper Dean Henderson was off his line quickly and he beat Grabban to it and cleared the danger.
Ten minutes before half time, Matty Cash found space 25 yards out but his shot deflected out off defender Jack O’Connell.
The Forest fans appealed for handball but referee Scott Duncan was having none of it, instead pointing for a Reds corner.
The 42nd minute produced arguably the best chance of the first half. A Sheffield United corner went deep to the far post where John Egan headed back across goal but the ball dropped just wide of the target.
Jack Robinson then nearly scored a stunning opener for Forest. The left back did well to keep a ball up with his first touch before volleying towards goal with his second, but it lacked the height or pace to really trouble Henderson who gathered comfortably.
Forest started the second half with a higher tempo and looked to win the ball back as soon as they could.
Jack Robinson did just that, winning the ball inside the Sheffield United half but his ball through Grabban was misplaced.
In the 57th minute, good work by Joe Lolley saw him slip through Matty Cash but his promising-looking effort was deflected away for a corner.
A floated ball towards the back post by Sheffield United in the 65th minute found Billy Sharp and he tried to direct his header towards strike partner Leon Clarke but the ball dropped wide for a goal kick.
The opening goal finally arrived in the 69th minute. Joao Carvalho did brilliantly to skip past his man on the left flank and he curled a teasing ball into the area which Lewis Grabban flicked into the back of the net.
There was almost a late, and cruel equaliser as Sheffield United applied the pressure in the closing stages.
Some pinball inside the Forest area saw the ball roll to Ben Woodburn but he couldn’t sort his feet out in time to direct the ball goal bound.
FOREST: Pantilimon; Darikwa, Figueiredo, Dawson, Robinson; Guedioura, Yacob; Cash (Dias 83), Carvalho, Lolley; Grabban (Ansarifard 90). SUBS NOT USED: Steele, Osborn, Janko, Tachtsidis, Hefele.
SHEFFIELD UNITED: Henderson, Stevens, Fleck, O’Connell, Clarke, Sharp, Egan, Coutts (McGoldrick 54), Norwood, Freeman (Baldock 80), Cranie (Woodburn 80). SUBS NOT USED: Moore, Stearman, Johnson, Washington.
REFEREE: Scott Duncan.
ATTENDANCE: 28,757 (1,976 away).
FOREST MAN-OF-THE-MATCH: Michael Dawson.