Boasting the fifth-best home record in the division, Paul Heckingbottom and his team will be bitterly disappointed that they couldn’t claim a result ahead of the second leg at the City Ground.
Goals either side of half-time from Jack Colback and Brennan Johnson gave Forest breathing space and Steve Cooper’s men could easily have had more goals having recorded 17 shots across the afternoon, eight of which were on target.
However, Sander Berge converted from close range following a corner in added time to halve the deficit and give the South Yorkshire side hope ahead of their trip to the East Midlands on Tuesday.
It was a thoroughly disappointing afternoon for the Blades, with wing-back Ben Osborn struggling against his former club.
The 27-year-old cruelly slipped in the penalty area to allow Philip Zinckernagel to have a shot from close range, with Colback burying the follow-up after a parry from United goalkeeper Wes Foderingham.
Moreover, there was limited defensive contribution from the Blades wing-back, who provided just one clearance, two interceptions and one tackle whilst winning only one of four attempted duels, making for a 75% failure rate.
Osborn also lost possession 12 times but his passing was generally impressive with an 84% success rate, whilst he also provided two key passes.
There had been debate prior to the match as to whether or not Heckingbottom would keep the 27-year-old in the starting line-up with George Baldock back fit. However, the Blades boss stuck with the side which beat Fulham 4-0 last weekend to secure a play-off spot, with Osborn playing on the opposite flank of his preferred left-hand side.
A decision must now be made by the 44-year-old as to whether or not he chooses to start Baldock on Tuesday in Osborn’s place, with the former making a return to action off the bench this afternoon.
Nonetheless, it was an afternoon to forget for Osborn, who sadly had a shocker against his former employers.