That blow came in the shape of a 3-1 loss away at Birmingham City, with Bryan Oviedo's late goal serving as a mere consolation.
The result meant that the Blues leapfrogged them out of the relegation zone, and Sunderland fell to 23rd with 25 points.
However, manager Chris Coleman then strengthened the squad with three additions on deadline day. Ovie Ejaria, Ashley Fletcher and Lee Camp joined from Liverpool, Middlesbrough and Cardiff City respectively, all on loan until the end of the season.
Following a bright start to the campaign, Ipswich Town look set for another mid-table finish in what is their 16th consecutive season in the second tier.
The Tractor Boys have accumulated 40 points from their 29 games and find themselves 12th in the table.
The January window has only served to increase the uncertainty around the future of the club, with Mustapha Carayol and Stephen Gleeson signing short-term deals until the summer.
Cameron Carter-Vickers also arrived from Tottenham Hotspur until the end of the season, replacing fan favourite Tommy Smith, who took up an offer to join MLS side Colorado Rapids.
They suffered defeat at the hands of league leaders Wolves last time out, where Matt Doherty's 15th-minute header was enough for the three points.
Lamine Koné is a doubt for the hosts having sustained a knee injury, but all three of their deadline day recruits are in contention to start.
Kazenga LuaLua should be fit having played half an hour at Birmingham, whilst John O'Shea has recovered from illness.
As for Ipswich, Cole Skuse returns to the squad having missed the defeat by Wolves through injury.
David McGoldrick is a doubt having not trained this week, but Cameron Carter Vickers has done so and is available for selection.
What they said
Chris Coleman spoke to the Northern Echo about his January dealings: "I'm happy with the business we've been able to do. It was brutal, so I'm glad it's done, but I think it's turned out good for us. We've injected some new faces in to the squad".
Town boss Mick McCarthy, who is of course returning to one of his former clubs, told the local press "It isn't going to be easy going to Sunderland", adding that the Wearsiders will "be desperate for the points on Saturday."
McCarthy added that he believes "there'll be a good atmosphere, certainly at the start" before stressing that his side must "silence that and they'll be up for it".