Sunderland were left punch-drunk on Boxing Day after suffering an embarrassingly straightforward 4-1 defeat to Manchester City for the second time this season.
A week before Dick Advocaat made the decision to leave the Stadium of Light, Manuel Pellegrini's side romped to a League Cup victory over the Black Cats and it was the same story at the Etihad Stadium, as a Kevin De Bruyne-inspired City swatted Sam Allardyce's men aside.
City toyed with Sunderland for long periods and could easily have secured a bigger victory after going 2-0 up inside the opening 22 minutes, through Raheem Sterling and Yaya Toure.
It got worse for Sunderland when Wilfried Bony headed home, before a fourth arrived from the excellent De Bruyne early in the second half, as City continually took advantage of some awful defending from the visitors.
Fabio Borini - one of the few Sunderland players to emerge with any credit - grabbed a consolation for his second goal in as many games, yet it did nothing to prevent Allardyce's men suffering a fourth successive defeat.
Vito Mannone made his first Premier League start of the season in a shock Sunderland line-up, which saw six changes from the side that suffered defeat at Chelsea.
Mannone was quickly picking the ball out of his own net, as for the third game on the spin, Sunderland fell behind inside the opening 15 minutes after 5ft 7in Sterling was able to head home.
Patrick van Aanholt was far too slow to close down De Bruyne to Aleksandar Kolarov's cross and the Belgian's delivery was met by Sterling, who got above Billy Jones six yards out.
Sunderland fell 2-0 down in the 17th minute as Jordi Gomez allowed Toure to twist and turn 25 yards out, before getting a left-foot shot away, with the ball skidding off the turf into the bottom corner.
Three minutes later, Danny Graham was a whisker away from halving the deficit when he met Borini's right-wing cross with a diving header that drifted agonisingly wide.
But Sunderland were 3-0 down in the 22th minute when Bony comfortably got above John O'Shea to head De Bruyne's free-kick into the corner.
City started the second half in the same tone - Mannone produced a superb finger-tip save in the 48th minute to deny David Silva after the Spaniard had played a sublime one-two with De Bruyne.
It didn't take them long to add a fourth though, the hugely impressive De Bruyne netting it in the 54th minute when his attempted through-ball came back to him off Sebastian Coates, before he tucked it beyond Mannone.
However, Sunderland pulled one back five minutes later when substitute Lee Cattermole's scuffed shot completely deceived the City defence.
Borini beat the offside trap and after his initial shot was saved by Joe Hart, the Italian tucked away at the second attempt for his second in as many games.
City spurned the chance to make it 5-1 in the 69th minute when referee Anthony Taylor awarded the hosts a spot-kick, despite Coates' foul on Silva appearing to be outside the area.
However, Bony's resulting penalty was awful as he skied it way over the bar.
The former Swansea man put another shot over the bar with 10 minutes to go when he shanked an effort from six yards out after Mannone had saved De Bruyne's effort.
Manchester City: Hart, Sagna, Otamendi (Kompany 61, Demichelis 71), Mangala, Kolarov, Fernandinho, Toure (Delph 62), De Bruyne, Silva, Sterling, Bony. Subs not used: Caballero, Clichy, Navas, Aguero. Booked: Sterling (4)
Sunderland: Mannone, Jones, O'Shea, Coates, van Aanholt, M'Vila (Cattermole 56), Gomez, Johnson, Borini, Fletcher (Lens 62), Graham (Watmore 71). Subs not used: Pantilimon, Brown, Toivonen, Defoe. Booked: Jones (36)