In front of a crowd of 1,734 - the second highest of the season – league officials were in attendance with the championship trophy but it had to remain under lock and key as second-placed Blyth Spartans also won to keep the title race going.
A win for Darlington coupled with Blyth failing to get a result against Rushall Olympic would have clinched the title for the Quakers, who raced into a 2-0 lead inside 25 minutes with goals from Leon Scott and Amar Purewal.
But Grantham refused to lie down and battled throughout. Despite Darlington's skipper Kevin Burgess rattling the Grantham crossbar with a header following a corner, the Gingerbreads finished the game the stronger but couldn't find a way through.
A win for Blyth meant the champagne remained on ice but Darlington need just a point from their two remaining games at Whitby Town on Thursday night and at Rushall on Saturday to clinch the title.
Blyth stretched the race into another game with a 3-0 success against the mid-table Pics.
Sean Reid opened Spartans` account after 18 minutes and Dan Maguire doubled their tally after 35 minutes. Michael Richardson ensured the three points with a third on 64 minutes to maintain Spartans` outside hopes.
Salford City are assured of one of the top five spots but who joins them and either Blyth or Darlington is still two from three after Workington AFC`s 4-1 Borough Park victory over Matlock Town.
It was a terrific evening for the Reds` Scott Allison, who followed up last Saturday`s winner at Ashton United with all four against the Gladiators.
He opened his and the Reds` account after 33 minutes and five minutes later made it 2-0. Charlie Dawes reduced the deficit two minutes later, only for Allison to complete a 10-minute hat-trick just before the break. He added a fourth with a minute of normal time remaining.
The win leaves Workington a point behind fourth-placed Ashton and fifth-placed Stourbridge, who possess a game in hand.
Ashton moved into fourth spot after a 3-0 Hurst Cross win against mid-table Halesowen Town.
Martin Pilkington opened the home side`s lead after 18 minutes and Jason Gorton added a second 10 minutes before the break. Chris Baguley ensured the points stayed on Tameside with a third 10 minutes from time.
The only other issue to settle is who joins Ramsbottom United and Colwyn Bay in dropping out of the Premier Division.
After Monday`s 4-0 defeat by Nantwich Town, Hyde United were condemned to back-to-back relegations after Whitby Town`s 2-1 Turnbull Ground victory over Barwell on Tuesday secured their safety.
Sam Hollis gave the visiting Canaries the lead on the half-hour mark, and it wasn`t until just shy of the hour-mark that the Seasiders got themselves back into the game, courtesy of Dale Hopson.
Barwell were reduced to ten-men with Liam Kay dismissed, allowing Whitby to take the lead in the 63rd minute through Adam Gell and hold on to ensure their place in the league next season.
The Seasiders and fifth-bottom Mickleover Sports, could both have been celebrating safety had Stamford AFC lost at Skelmersdale United.
However, the battling Daniels gave themselves the faintest hope of surviving the drop with a 4-1 victory at Stormy Corner.
The Daniels went behind in just the second minute too when Max Hazeldine struck for the hosts. However, Jordan Smith responded for the visitors just two minutes later.
Stamford, knowing anything less than a win would see them relegated, went on the attack and they got their reward. Jake Newman put them in the lead after 25 minutes and Greg Smith made it 3-1 after 33 minutes. In the second half Lee Beeson put his name on the scoresheet shortly after the hour-mark.
Stamford are now up to 21st position, three points behind Mickleover who play Nantwich on Wednesday night.
If Mickleover lose, the whole season will come down to a final day showdown between the two sides at the Zeeco Stadium on Saturday with goal difference the key factor.
Elsewhere on Tuesday, two of the relegated sides, Ramsbottom and Colwyn Bay, shared a 2-2 draw at the Harry Williams Riverside Stadium.
Jack Kelleher giving Bay a sixth minute lead that Jake Cliffe after 34 minutes and a Carl Rodgers own goal five minutes before the break, turned over. Jordan Harper`s 52nd minute equaliser ensured Bay earned a point.
Frickley Athletic will end the season wondering `what if` after they made it one defeat in eleven in a 2-0 success at Buxton's Silverlands, leaving the Blues in seventh spot.
Tom Davie after 34 minutes and Tyler Williams on 58 minutes sealed Frickley`s latest three points.
Sutton Coldfield Town eased to a 4-2 Coles Lane win over Marine AFC in the evening`s other game.
The Royals trailed 2-0 at half-time to Lewis Codling and Chad Whyte efforts within two minutes of each other just before the half-hour mark. But 2-0 can often prove to be a dangerous lead, and so it proved.
An own goal from Liam Goulding five minutes after the break set the Royals` reply off and six minutes later they were level through Aaron Forde. Dan O`Callaghan put the hosts in front on 67 minutes and James Beresford added a fourth six minutes from time.
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