A 2-1 home win over them on Boxing Day was rubbed out by a 5-3 away defeat the day after.
Panthers will feel they have the cornered the bragging rights - they were 5-1 up at one stage.
Meanwhile, Steelers form remains hard to analyse.
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They have won six of their last eight...or one out of their last three, depending on how you read the stats.
Panthers largely dominated the middle period in the Sunday game, scoring two unanswered goals when they were already 2-1 up - then adding a fifth in the 42nd minutes.
It left a mountain to climb. And while Sheffield pulled a couple back, this will be another Christmas where the honours, effectively, went to one of Sheffield’s biggest title rivals.
The teams may have split the points but Notts regained the loftier league place and will feel they had more of the game on both nights.
Sunday, in real terms, was an opportunity - as well as a game - lost, for the South Yorkshire team.
For the second night running, Nottingham took the lead early on, this time after just 92 seconds, David Clarke sparking delirium among Panthers fans at the NIC with a shot from an acute angle.
Jonathan Phillips, revelling in his return to action after surgery, almost got Sheffield back on level terms but Miika Wiikman, rested the night before, deflected the shot over.
And recent history repeated itself when Dowd scored on the Power Play, punishing Andy Bohmbach’s hooking minor, and slotting past a prostate Wiikman at 11;42.
Panthers’ David Ling hit the post and then went ahead for the third time of the weekend; Canadian centre Logan MacMillan making it 2-1 for the home side.
It was altogether a more heated occasion than 24 hours earlier: 22 first period shots on both goals, Levi Nelson and Robert Farmer handed 2+ 10 minute and Juraj Kolnick same punishment for a check to Cullen Eddy’s head.
Marek Pinc prevented Panthers widening their gap with saves from Evan Mosey and Brad Moran, but he was helpless when Chris Lawrence cycled his way into a shooting position to make it 3-1, via Cam Janssen, at 32.57. The defence? Non existent.
Tempers snapped on the bench and visiting coach Paul Thompson received two minutes for abuse of official.
Panthers took the opportunity with both hands and with Steelers failing twice to clear the puck, Clarke helped himself to his second.
Down by four to one and it’s all your fault: that was the message to Thompson from the NIC ranks. Could Steelers stem the bleeding? No, they went 5-1 down two minutes into the last session, Sam Oakford a bit of a fluke - but they all count.
Sheffield’s Colton Fretter appeared to out the picture through injury, as was Mathieu Roy, but the side did manage to show some spirit at 43.58 when Levi Nelson made it 5-2.
And Jason Hewitt - a player Steelers can always count on in such ‘derbies’ - drove the net to grab Sheffield’s third.
n On Boxing Day, Panthers appeared the stronger force in the first period - you have to give them credit for the way they took the game to Sheffield on Steelers’ own ice with 9,000 fans in the building.
With Sheffield defending remarkably deeply, Marek Pinc had been under pressure, and the goalie was first to be beaten, by MacMillan, at 7;38.
Filled with confidence, Panthers went looking for a second - they clearly fancied their second successive Boxing Day win at Sheffield Arena.
But were rocked on their heels eight minutes later when Rod Sarich motored in and shot spectacularly past Dan Green.
Steelers had a touch of luck when Kolnick threatened, but his stick broke in two during his shot.
In truth, there was little between the sides for the rest of the game, which Thompson rightly described as a chess match.
It was won by Dowd’s bullet shot from the blue line on the Power Play, which zipped past Panthers’ starting back-up.
Nails were chewed down to the bone in the stands and on the bench - it wasn’t pretty, but it was effective, with Pinc and Sarich the outstanding performers.
Lawrence, the centreman who has played for both clubs this season, flickered in and out of the game, but he was never able to make a significant impact on Sheffield’s defence.
With four minutes remaining Sheffield forward Fredrik Vestberg- rarely in trouble with any referee - intelligently took a hooking penalty with Bohmbach seemingly about to equalise - and Steelers killed the penalty and won the match.
Panthers’ boss Corey Neilson thought his side had been the better “all night long.”
“We just never got a bounce or a break. We never got that final goal or shot to take the game.”