United kept a clean sheet and thoroughly earned a share of the spoils in Tuesday evening's fixture at league leaders Burton Albion.
Both sides had chances, Billy Sharp and Martyn Woolford with the best for the Blades, as both sides recorded their first stalemate of the season.
Boss Adkins made two enforced changes with Alcock (hip) and Baxter (groin) missing out - Freeman and Reed were the replacements. Done was named on the bench for the first time this season.
The opening half hour was cagey as neither side looked to give anything away. Duffy looped a weak half-volley wide, whilst El Khayati and Butcher were both off target with shots from the edge of the box after swift breaks. Sammon was heavily involved in United's first half attacking prowess and he appealed for a penalty after 25 minutes when he fell under the attentions of two defenders from a Freeman cross.
El Khayati was on target with his next effort but Howard saved comfortably, whilst Basham's flicked header from Wallace's cross drifted wide.
As half-time approached United had the greater share of possession but Burton remained disciplined defensively, even when Basham, Sharp and Freeman linked up, which forced Mousinho to clear over his own crossbar. From the resulting corner, Basham tried to force the ball home at the near post.
The start of the second half was more entertaining than the first with United again attempting to get on top. Sharp fired over after Wallace broke up a Burton move and started one for the Blades, a number of crosses also put the home side under pressure.
Burton hit back with a couple of good chances, both falling to the same man. El Khayati lost Basham but fired at Howard and then he sidefooted over on 58 minutes after latching on to Duffy's low cross.
On the hour Sharp anticipated McCrory's back header falling short but the striker was crowded out by goalkeeper McLaughlin, whilst the resulting corner saw Burton force the ball clear after Edgar's back heel.
Adkins introduced fresh legs in wide positions when he threw on Scougall and Woolford and crosses continued to be plan. As the final 15 minutes approached, the game was considerably more open than the first period and Mousinho went close to converting El Khayati's corner at the front post.
Woolford cut in from the right and fired wide and moments later, on 87 minutes, he did the same following Freeman's lay-off, but McLaughlin touched around a post.
McNulty replaced Sharp for the closing stages but the remaining attacks, in the three added minutes, came from the home side, although Howard was not tested with Collins winning a string of headers as United's disciplined display earned a deserved point.
Blades: Howard, Freeman, Basham, Flynn (Woolford 62), Coutts (Scougall 62), Sharp (McNulty 89), Collins, Sammon, Reed, K Wallace, Edgar.
Unused: Done, Long, Kennedy, Dimaio.
Burton: McLaughlin, Edwards, Mousinho, Weir, Beavon, El Khayati, Butcher (Naylor 86), McCrory, O'Connor, Duffy (Thiele 90), Binniom-Williams (Akins 45).
Unused: Cansdell-Sherriff, Joachim, Palmer, Matthews.