There was just one change to the side which beat Manchester City 2-0 last Friday, Leicester's fourth consecutive victory in all competitions, as Filip Benković came in for Khanya Leshabela.
The Foxes carved out the first opportunity of the clash at Stadium of Light within just 10 minutes as Dewsbury-Hall’s corner was glanced agonisingly wide by Callum Wright.
Laurens De Bock, meanwhile, went for goal from distance for the Black Cats, currently seventh in Sky Bet League 1, but Viktor Johansson was able to smother it at the second attempt.
Phil Parkinson’s hosts struck after 14 minutes, though, as Chris Maguire produced a free-kick almost identical to the one he hit in a recent 5-0 win over Tranmere Rovers into the near corner.
As City looked to work a way back into the game, George Thomas’ free-kick was saved by Jon McLaughlin, while Admiral Muskwe appeared to be through before Alim Öztürk saw it out.
Top scorer Hirst, on the other hand, was played in behind Sunderland’s backline by Dewsbury-Hall, but the England youth international was unable to get a shot off at goal.
After the break, Leicester upped the tempo in dramatic style, completing a three-minute turnaround in fortunes which saw them take a lead over their League 1 hosts in the North East.
Firstly, the visitors were handed a precious opportunity to level the scores on 50 minutes as Wright was felled in the area, with Hirst making no mistake from the penalty spot.
After the 20-year-old’s cool finish into the bottom corner, City pushed for another and they were rewarded as Dewsbury-Hall launched a stunning rocket into the top corner from the edge of the area.
With seconds of normal time remaining, the Black Cats were desperately unlucky not to level it when Johansson tipped it into Grant Leadbitter's path, but his half-volley bounced up and over.
Major moment
With a slight delay before stepping up for his spot-kick, George Hirst needed to show composure to haul Leicester back into the contest.
The in-form striker made no mistake, netting his sixth goal of the season in all competitions, to set in motion a series of events which led to a hard-earned victory.
Who impressed?
While Kiernan Dewsbury-Hall’s goal will attract attention, the Leicester-local was once again in fine form in the North East, marshalling the midfield alongside George Thomas.
It was his industry in the middle of the park which allowed others, including Thomas, to base their attacks on. His goal, on the other hand, was a special example of his technical ability.
Where does it leave us?
Leicester retain their position at the summit of Northern Group A and seal safe passage into the knockout phase of the competition, despite Sunderland and Scunthorpe meeting next week.
Following their final group stage fixture, the Foxes are on eight points, five above Sunderland and four clear of second-place Scunthorpe. Grimsby, on the other hand, finish bottom with zero.
Coming up…
City’s youngsters have just under a three-week break until their next outing – a Premier League 2 Division 1 clash with Derby County at Holmes Park.
The Rams visit Holmes Park on Monday 25 November (7pm GMT kick-off) – an encounter you can watch for free on LCFC TV.
The details…
City: Johansson; Clark, Johnson, Benković, Ughelumba, L. Thomas; G. Thomas (c), Dewsbury-Hall, Wright (Leshabela 83'); Hirst, Muskwe (Eppiah 69')
Subs not used: Davies, D. Gyamfi, Kranthove, Tee, Arlott-John
Goals: Hirst (p) 50’, Dewsbury-Hall 53’
Attendance: 7,649