The Window Centre Tigers staged a stunning fightback to emerge with three SGB Championship points.
They trailed by eight points after just three heats but came on strong in the closing stages to shock their play-off rivals in a tense encounter.
No 1 Josh Grajczonek was once again the last-heat hero, seeing off former Tigers man Ricky Wells to take the chequered flag and see them over the line.
Skipper Kyle Howarth suffered an engine failure in the final race, but his heat 13 win over Wells, backed up by a third place for Howarth, eventually proved decisive after giving them the lead.
The visitors quickly got dialled in at the Cumbria track and had plenty of firepower with 10 race winners on the night.
Grajczonek was in fine form, taking the chequered flag on three occasions and top scoring with 12 points.
Howarth also won three of his first four outings, ending their poor start with a heat four success to settle any Sheffield nerves.
Middle order man Lasse Bjerre bounced back from a tapes exclusion in his opening ride to win his final two outings.
He was partnered by Josh Bates in heat 10 for a pivotal 5-1 which got their side back in contention, whilst Aussie ace Todd Kurtz won heat eight on his way to a solid five points.
It was a perfect response from Simon Stead’s side after their hammering at Glasgow.
The result moves them within two points of the top four, with three meetings in hand on Redcar.
They will be back in action with at Ipswich on Wednesday (7.30) then hosting Berwick at Owlerton on Thursday (7.30).
* The scores -
WORKINGTON 44: Ty Proctor 11+1, Ricky Wells 8+1, Thomas Jorgensen 7, Danny Ayres 6+1, Mason Campton 6, Matt Williamson 4+2, Rob Shuttleworth 2+1.
SHEFFIELD 46: Josh Grajczonek 12, Kyle Howarth 11, Lasse Bjerre 8+1, Josh Bates 7+1, Todd Kurtz 5, Rob Branford 3, Nathan Stoneman 0.