Managerless Sunderland followed last week's 6-0 humiliation at Bolton with a 2-1 humbling at home to bottom-of-the-table Doncaster Rovers.
The Black Cats let down a crowd of more than 38,000 who had turned out to welcome returning hero Jermain Defoe, who re-signed for the club on deadline day.
But while there were cheers for Defoe, there were boos at half-time and full-time after Sunderland turned in another awful performance.
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Doncaster debutant Reo Griffiths gave the visitors the lead midway through the first half, and Tommy Rowe added the second in injury-time at the end of the first period.
Between those goals, Doncaster hit the post and had numerous other chances to extend their lead.
Sunderland were better in the second half and had the linesman awarded a goal when Ross Stewart's header appeared to cross the line on the hour, it might have been a turning point, or had Elliot Embleton's shot gone in rather than hit the post soon afterwards.
But instead, they had to wait until the final minute of the 90 before Corry Evans pulled one back and by then it was too late.
Sunderland dropped to fourth in the table, and the pressure is on sporting director Kristjaan Speakman to bring in a new head coach - with the fans making their feelings plain, chanting Roy Keane's name at times during the match.
With Lee Johnson sacked on Sunday, interim bosses Mike Dodds and Michael Proctor made one change to the starting line-up that began the 6-0 thrashing at Bolton Wanderers a week ago.
Alex Pritchard came into the side, with Leon Dajaku making way.
Deadline day signings Defoe and Jay Matete were included on the bench, and made their entrances with around 20 minutes to go.
Doncaster boss Gary McSheffrey made four changes, in his case to the side that started the midweek 5-0 home defeat against Rotherham United.
New signings Griffiths and Ben Jackson made their full debuts, while Josh Martin and Ro-Shaun Williams also came into the side, in place of Kyle Knoyle, Branden Horton, Joe Dodoo, and Adam Clayton.
Sunderland were absymal in the first half, carrying on exactly where they left off at Bolton the prevuious week.
They looked leggy and one-paced, and that allowed Doncaster to take control of the game.
After a couple of half-hearted efforts at each end, it was the visitors who took the lead on 22 minutes.
Martin collected the ball midway inside the Sunderland half and his ball over the top caught the defence square, and Griffiths raced through into the area to slot low past Thorben Hoffmann, who was slow to react.
Doncaster almost added a second on the half-hour when a free-kick from Martin was parried unconvincingly by Hoffmann diving low to his left, but when Joseph Olowu pounced on the loose ball the angle was tight and his shot hit the keeper and went behind.
And a minute later, Doncaster again went close when Charlie Seaman found space inside the area to shoot, but his effort came back off the left-hand post.
Stewart headed wide from a Pritchard cross following a short corner, and Elliott Embleton scuffed a shot wide from inside the six-yard area.
But Doncaster added a third in injury time at the end of the first period, when Sunderland failed to clear their lines properly from a corner and when the ball came back into the box, Rowe blasted his finish high into the roof of the net.
Sunderland improved in the second half, albeit from a very low base.
A neat turn and shot from Pritchard just outside the box brought a good save out of Johnny Mitchell within a couple of minutes of the restart.
A few minutes later, Dan Neil brought a spectacular diving save from Mitchell with a fierce shot from 25 yards out.
At the other end, Hoffmann had to get down smartly to his left to save from Rowe.
On the hour came the moment of controversy when Pritchard crossed from the left and found Stewart at the far post, his downward header looked to have crossed the line before Mitchell could scoop it clear but the linesman did not indicate a goal and play continued, much to the fury of the Sunderland fans.
Midway through the second period, Embleton struck the left-hand post with a curling left-foot shot from outside the box.
And a few minutes later, Defoe and Matete were thrown on as Sunderland went in search of a goal to get back into the game.
Danny Batth headed narrowly wide as time ticked down, but Sunderland finall pulled a goal back a minute from the end.
A low shot from Pritchard was parried by the keeper straight into Evans' path inside the six-yard box, which presented him with a tap-in, but it was too little, too late for Sunderland.
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How they lined up
Sunderland: Hoffmann, Winchester (Clarke 61), Batth, Doyle, Gooch, Evans, Neil (Matete 73), Cirkin, Pritchard, Embleton (Defoe 73), Stewart. Subs not used: Patterson, Dajaku, Hume, Roberts
Booked: Evans
Doncaster: Mitchell, Williams, Oluwu, Younger, Seaman, Smith, Rowe, Jackson, Martin (Gardner 69), Odubeko (Dodoo 74), Griffiths (Knoyle 80). Subs not used: Jones, Clayton, Barlow, Agard
Referee: Will Finnie (Bedfordshire)
Attendance: 38,395
