The visitors came into today's fixture heavily on the decline, clearly eyeing an encounter with the top flight's basement boys as the springboard needed to get their league form back on track.
Sunderland, on the other hand, came into the game haven recently experienced back-to-back wins and a dignified loss away at Liverpool. A hitherto scarce sense of confidence was emanating around the Stadium of Light.
Jan Kirchhoff made his return to the home side's bench, and Moyes opted for the younger legs of Papy Djilobodji in the heart of defence over the experience of John O'Shea.
Sunderland certainly started the better of the two sides - having the first few chances of the game as Victor Anichebe first sent the ball skyward after some well-worked passing, and had his shot blocked when the lads broke forward minutes later.
Steven Pienaar was running the show in the center of the park, practically turning Patrick van Aanholt into his new Leighton Baines as he sent the Dutchman marauding down the wing - causing plenty of issues for the foxes.
For the first twenty minutes it was all Sunderland. Van Aanholt and Billy Jones both making waves down the flanks, but with the final ball being consistently ineffective.
Anichebe's best chance of the first half came when be characteristically barged his way through the defence only to have his shot blocked once again, the subsequent rebound fell to Watmore, who also found his shot deflected.
As the first half ticked on, however, Leicester gradually found their way back into the game. Pickford almost dropped a clanger as he fumbled a seemingly harmless cross from Marc Albrighton.
A free-kick from the visitors nearly resulted in them taking the lead as Christian Fuchs broke away from the wall to nab a free header, but thankfully his effort drifted wide of the far post.
Sunderland had a couple of injury scares as the first forty-five minutes drew to a close, Big Vic started limping and Albrighton collided with Pienaar with the latter coming off worse.
The home side were spared of any added-time angst as Fuchs floated in another cross that dipped dangerously. Much to the delight of a stranded Jordan Pickford, the ball bounced off the bar and away from danger.
Moyes made two changes after the restart as Jason Denayer and Steven Pienaar were replaced by veterans of injury Seb Larsson and Jan Kirchhoff.
The first chance of the restart came when Islam Slimani was slipped in with a dangerous low cross, but his snapshot was dealt with by the reflexes of Djilobodji.
For the first ten minutes or so the scales were evenly balanced as both sides seemed competent, but the deadlock would be broken by the home side.
Sunderland won a corner in the sixty-fourth minute, big Jan Kirchhoff rose highest to meet the delivery, and his glancing header bounced off Robert Huth and into the net. The lads took the lead through an own goal.
Minutes later Sunderland were denied a golden opportunity to double their advantage. Danny Simpson brought down van Aanholt in the box but all penalty appeals were waved away. Simpson appeared to clip the Dutchman's heels in the aftermath of the initial challenge, but the referee didn't deem it worthy of handing the home side a spot-kick.
But that minor setback did nothing to dampen the lads' spirits - as the crowd roared them on, the Black Cats continued to claw at the Foxes' defense. It wasn't long before their persistence was rewarded again.
Anichebe marauded down the flank and squared the ball to Watmore, whose effort was parried by Ron-Robert Zieler. But who else would be first to react to the rebound than Jermain Defoe? The veteran striker turned the subsequent effort into the back of the net with all the finesse we expect from him.
However, as we all know in our following of Sunderland, nothing is ever that comfortable.
Shinji Okazaki pulled one back with the devious finish only minutes after Sunderland went two ahead. The Japanese frontman timed his run perfectly with Demarai Gray's cross and slid the ball into the far corner to make it 2-1.
But there would be no repeat of the Crystal Palace match this time, Sunderland would remain defensively resilient and steer the ship toward our third win in four matches. Our fortunes have been well and truly turned around.
FT: Sunderland 2 - 1 Leicester City (Huth OG 64', Defoe 76', Okazaki 79')
Sunderland: Pickford, Jones, Kone, Djilobodji, van Aanholt, Pienaar (for Kirchhoff 45'), Ndong, Denayer (for Larsson 45'), Anichebe, Defoe, Watmore (for Manquillo 84')
Subs: Mannone, Larsson (for Denayer 45'), Kahzri, O'Shea, Manquillo (for Watmore 84'), Kirchhoff (for Pienaar 45'), Januzaj
Leicester: Zieler, Simpson, Morgan, Huth, Fuchs, Mahrez (for Musa 73'), Amartey, King, Albrighton (for Gray 73'), Slimani (for Okazaki 68'), Vardy,
Subs: Hernandez, Musa (for Mahrez 73'), Hamer, Schlupp, Okazaki (for Slimani 68'), Gray (for Albrighton 73'), Mendy