Siddons' goal accounted for visiting Corby Town in front of a crowd of more than 500 for the Northern Premier League Midlands Division match. The Daniels had to dig deep to defeat their derby rivals with another much-changed line-up as they handed a second debut to the returning Jake Duffy who had been skipper of the Steelmen until his transfer on Friday.
Tom Siddons also started in place of Cameron Johnson against a Corby side that included former Stamford players Curtis Hartley and Elliot Sandy. And it took Siddons just six minutes to mark his return to the Stamford starting line-up when he put the Daniels ahead.
A slide-rule pass from Jack Duffy after Jake Duffy had made a fine tackle to win possession set Cosmos Matwasa free and, although his shot was saved by Nemanja Grubor, Siddons pounced on the rebound to give Stamford the lead. The Daniels looked to increase their lead with a last-ditch tackle from Jake Holt denying the marauding Jack Duffy before Joe Butterworth sent a well-struck strike just wide of the visiting goal.
Corby's best opening of the half came from a free-kick by Jordan O'Brien after he had been fouled but Stamford goalkeeper Dan Wallis was equal to the well-struck shot with a comfortable save. Stamford were then forced into a change midway through the half when the in-form Jack Duffy went off injured to be replaced by Rodrigo Goncalves.
Goncalves almost had an instant impact as he chased a Jake Duffy through ball and the keeper's hurried clearance was collected by Siddons who looped his shot wide.
Cosmos Matwasa was always a threat to the Corby defence with his forceful runs and he had a cross-shot tipped away by Grubor after another lively burst. Ed Cook then headed wide when well-placed from the resultant corner before Goncalves fired another shot narrowly past the Corby goal as Stamford finished the half on top.
The Daniels had two good chances at the start of the second half to increase their lead as firstly skipper Sean Wright was thwarted by a fine save from Grubor who kept out his header from a Harry Vince free-kick before Holt made a crucial covering run to rob Matwasa as he rounded the Corby custodian. Siddons agonisingly failed to get onto the end of an inviting cross from Stacey Freeman as Stamford desperately needed a second goal to end Corby's hopes.
The Steelman put several dangerous crosses into the home box but the Daniels defended well with Vince coming to his side's rescue by heading off the line to deny Sandy. O'Brien then tested Wallis from distance as the visitors continued to probe for an equaliser as Stamford try to hit them on the break.
Corby's cause was then hampered deep into injury time when Ilias Labiad was red-carded for a two-footed challenge and Stamford were able to see out the four minutes of stoppage time.