And only the woodwork prevented the Blades, who had lost all six previous League One trips this term, from claiming a shock success at London Road in what is almost certain to have been interim boss Chris Morgan's final game in temporary charge.
Lyle Taylor thundered a 20-yard blast against the crossbar eight minutes before the break with Posh goalkeeper Bobby Olejnik rooted to the spot before Febian Brandy dragged a decent opportunity across the face of goal later in the same attack.
They were rare moments of action in a lacklustre contest.
The home side's best chance arrived early on when skipper Tommy Rowe was denied by a smart George Long save at his near post.
The Blades keeper was not required to make another noteworthy save until keeping out Ipswich loanee Paul Taylor after the break.
Posh kept a fifth successive clean sheet but rarely looked like pocketing maximum points despite cranking up the pressure in the closing stages.