Steelers started off 2018 with a pulsating overtime win at Manchester, having earlier taken the lead three times.
The all action match was one of the games of the season - but it will be the two points that Sheffield will treasure most.
Andreas Valdix scored the penalty shot winner to earn the victory.
Ervins Mustukovs’ history-making run of shut outs ended 12 minutes and 51 seconds into the game, when American defenceman Ryan Trenz scored unassisted.
Before then, the Latvian had made some of his customary spectacular saves, while at the other end, his side had threatened through Matt Marquardt and Andreas Jamtin.
Steelers forced their way back, though, with top scorer Robert Dowd smacking in his fourth goal in three games, assists going to Marquardt and Mark Matheson (17:09.)
And Storm were rocked 10 seconds from the first break when Mathieu Roy converted an enterprising play from Colton Fretter.
Steelers, who saw off Storm 3-0 on Saturday, had stunned the home crowd who made up a new attendance Storm record in their present guise.
But Ryan Finnerty’s side came out with a sharpened mentality and they levelled when Luke Moffatt manouevred around Davey Phillips and directed the puck home for 2-2, at 21;52.
Paul Thompson, in his 200th game in charge of Steelers, had spoken before the match about encouraging signs of improvement and they were visible again with a second power play goal, Miika Franssila scoring from Jonas Westerling, and Fretter at the half way point.
Defensively, Sheffield have been admirable recently and their penalty killers saw off a five on three Storm advantage, with Ben O’Connor and Jamtin serving minors.
But Manchester dragged themselves level for a second time through one-time USA U18 national team player Moffatt, when he wrist shot just managed to beat Mustukovs at 38:51, on a delayed penalty play.
Sheffield without suspended Tim Wallace (Storm captain Jay Roseshill was also banned) took just 21 seconds to reassert their advantage, an unmarked Fretter benefiting from Jamtin’s work on the flank.
But the eighth goal of the see-saw game went to hat-trick man Moffatt, who had been plyng his trade in Europe before joining Storm this season. His 43rd minute strike further ignited the noisy home fans and they were rewarded a minute later by Storm’s fifth of the night, from Gerard Hanson.
Mike Clemente’s glove stopped Valdix as Sheffield tried to rescue themselves.
with seven and a half minutes to go Steelers went on the power play with Mike Hammond serving a slashing minor.
After falling behind, it was time to go back to work.
But Storm’s positional sense and forechecking denied them the opportunities they were looking for.
At 54.38, Sheffield were granted another go, with Linden Springer going for cross checking.
That was seized upon by Roy, levelling at 5-5 at 55:53.
Marquardt and Ben O’Connor could have won it in regulation, but the cracker of a game went into overtime, a session which saw Mustukovs at his best and Roy and Levi Nelson closed to winning it.
Instead it went to penalty shots - and Valdix had the last word for third-in-the-league Sheffield.
Monday 1st January
Coventry Blaze 1 Nottingham Panthers 2
Manchester Storm 5 Sheffield Steelers 6 (After Penalty Shootout)
Milton Keynes Lightning 0 Cardiff Devils 5
Tuesday 2nd January
Dundee Stars v Braehead Clan - 7.30pm
Guildford Flames v Edinburgh Capitals - 7.30pm
Wednesday 3rd January
Fife Flyers v Manchester Storm - 7.00pm
Challenge Cup Quarter Final 2nd Leg
Nottingham Panthers (1) v Milton Keynes Lightning (2) - 7.30pm