Taking a less familiar striking role, Johnson caused problems all night for an inexperienced Blades backline, showing glimpses of what could be a crucial contribution if the Owls are to avoid the drop this season.
United fielded a youthful side as the majority of the reserve regulars were in Hungary for Tuesday night's friendly against Ferencvaros.
Wednesday included several other first team regulars; Etienne Esajas and Steve Watson both continuing their recovery from injuries.
But it was Burton O'Brien who opened the scoring for Owls on 12 minutes, catching the Blades defence off guard from a quick free-kick.
After tricky play down the right, Johnson cut in and was felled on the edge of the box. As United's keeper Kang Ho Lee was lining up the wall, O'Brien struck the ball sweetly into the unguarded bottom right corner.
The Owls doubled their lead on 21 minutes, with Johnson again instrumental.
After surging down the right wing he cut inside and delivered a perfect ball to unmarked Ronnie Wallwork who headed home.
The youthful Blades outfit were full of running, Algerian Youth international Aymen Tahar standing out, but ultimately lacked a cutting edge as the half drew to a close.
Todd Wood replaced Esajas for Wednesday at half-time, and the Dutchman was happy with the run out.
He said: "The foot felt good but it was strange in the beginning. It was much harder than training in the gym which is all I've been doing for two months."
After the break Johnson's pace continued wreak havoc and forced Wednesday's third goal on 62 minutes.
What do you think? Post your comments below. After surging through the backline he rounded the keeper and squared for Luke Boden, whose finish powered past the covering defender on to the underside of the bar and in.
At times the Blades played some neat football just without the end product and United coach Kevin Fogg was proud of the team's performance.
He said: "For a lot of the match we took the game to a team with more experienced players.
"In the end it was a good learning experience, the lads never dipped their heads".
Sheff Utd: Ho Lee, Walker, Binnion, Eagers, Chapman, Lowton, Askham, Quinn, Oliver, Boden, Tahar. Subs: Reid, Furniss, Smith, S-Latef, Rhodes
Sheff Wed: Burch, McMenamin, Gilbert, Wallwork, Watson, Liversidge, R Lekaj, O'Brien, Johnson, Boden, Esajas (T Wood ht). Unused subs: Hadfield, Pratt, Harrison, Bowman.
Attendance: 269
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The full article contains 504 words and appears in Sheffield Star newspaper.