United's Under 23s fell to a narrow and frustrating defeat away at Nottingham Forest despite creating plenty of chances during a thwarted second half comeback.
Forest had taken the lead early on after largely dominating the first 20 minutes and when a cross came in from the left it appeared to be bundled home by a combination of the Forest striker and Blades defender Keenan Ferguson.
Jake Eastwood stood tall to deny Forest a certain second soon after and from there on it was United who had control of the match for large parts.
There were few chances to speak of before the break as the Blades simply looked to gain a foothold in the match but after the half-time interval it was a different story.
Oli Greaves, the star of Friday's win against Doncaster, saw two half chances saved by the goalkeeper before Conor Washington came closest of all, Bossin saving his neat flick from point-blank from Harry Sheppeard's teasing cross.
Reece York was also denied by Bossin after he found some room for himself inside the box but the ball just wasn't falling for United
The Blades would go closer still with less than 10 minutes to go and this time it was a double save from Bossin that would deny them.
Harry Boyes did well to win a 50/50 down the left and his low drive was parried by Bossin, only for the keeper to pick himself up and deny Simeon Oure on the rebound.
Despite plenty of pressure and balls into the box, United couldn't find a late breakthrough as Forest held on for the three points.
Blades: Eastwood, Ferguson, Belehouan (Bennett 59), Bryan (Williams 46), Boyes, Sheppeard, York, Neal (Oure 63), Lundstram, Greaves, Washington.
Unused: S. Kelly, Ackroyd.