For the fourth game running United took all three points with a comfortable win without conceding a single goal.
This run of games against teams in the lower half of the table has meant United have now closed the gap on leaders Mansfield Town to just three points now, with four games in hand.
With both Rachel Ruddach and Christina Skull unavailable, Jodie Hartley moved into the heart of the midfield for this one whilst experienced striker Tania Marsden was needing just one more goal for her 100th for United.
Eighth place Arnold Town were playing United for the first time and had former Blades forward Melissa Renshaw in their ranks.
United soon got into their passing game and began bombarding shots at the visitors goal. The inter changing between players was admirable setting up each in turn. Jen Pearson had three shots as did Kim Brown and Jorden Spurr from distance. It was suprising it took United 33 minutes to score given the dominance and it was Pearson who squared to Brown to finally break the deadlock.
However, it was Marsden who had three tremendous chances amongst others to get that 100th career goal, twice put through only to fire over and when Pearson crossed from the byline Marsden could only deflect the ball wide from only a few feet out.
After the break United resumed their dominance, Paige Wainwright having an early drive just wide from right-back. 52 minutes in, though, the milestone 100th goal was finally reached when Marsden smashed the ball home from the six yard line to make it 2-0.
She had made her team wait after her usually lethal finishing had deserted her in the first half but normal service had been restored. Marsden has been a great servant to United since joining from Wednesday in 2009, voted Players' Player of the year in 2011 and top scorer the last time United were promoted in 2012 with 34 goals in her most prolific season.
United promptly scored again two minutes later to put the game beyond Arnold Town when Jodie Hartley fired in the third in similar fashion to her goal the previous week. Shortly after this Arnold came closest to pulling a goal back when they struck the United crossbar from a free-kick. Thereafter 'keeper Kirsty Johnson had a fairly comfortable time and pushed the length of time on a clean sheet up to 365 minutes by the end.
United continued to push for more goals, Arnold giving spirited resistance. Brown dribbled into the box to finish on 70 minutes for her second of the game and 19th of the season. United's substitutes Annalise Carroll, Shannon Smith and Melissa Celi kept the pressure on Arnold's defence who had been pressured throughout. Deep into injury time, after three stoppages had created over seven minutes of additional time, Wainwright popped up unmarked at a corner to head United's fifth.
This coming Sunday United host Northampton Town in the League Cup quarter-final at the United Academy.
Blades: Johnson, Wainwright, Cawthorne, Froggatt, Hopkinson, Bell (Celi), Spurr (Smith), Hartley, Pearson, Brown, Marsden (Carroll).