With just eight games left of the season, the 20th-placed side are losing their relegation battle, and manager Chris Coleman admitted post-game via Chronicle Live that the weekend defeat was a big opportunity missed.
In his words: “Today was an opportunity, the biggest one we have had, to close that gap, and we didn’t take it.
“I was here in my room and I was keeping an eye on it [Barnsley’s game].....It was a great result for us, but not now – it was another missed opportunity."
The former Wales boss took charge of Sunderland last November, but hasn't been able to improve the club's fortunes.
Since Coleman took over, the Black Cats have managed just four victories, drawn five times and lost 12 other league games.
In the event that Sunderland do get relegated without putting up a fight, Coleman's reputation will surely take a hit, and some fans are wondering why he left the Wales job in the first place.
Here are few Sunderland fan reactions on Twitter:
Wonder how much Chris Coleman regrets leaving his cushy Wales job for Sunderland? Going from asking Bale and co to beat Luxembourg and the likes a few times a year, to getting whacked in the Championship every week, at a half empty stadium, with zero financial backing— Molly Shepherd-Boden (@MollyShep) March 18, 2018
3months on can somebody please tell me what on earth Chris Coleman was on when he decided to leave Wales for Sunderland?— Andrew Williams (@andywills1019) March 18, 2018
Chris Coleman left a comfortable job at Wales go take over at Sunderland...— ⚫☛ 'RycoMDCXC' ☚⚫ (@RycoMDCXC) March 18, 2018
What was he actually thinking?
Is Chris Coleman completely blameless?— James Copley (@JamesCopley73) March 17, 2018
Or is there a fundamental issue at the club beyond his control?
Bit of both, maybe?
I’m torn. #SAFC
Chris Coleman managed Wales in a European Championship semi final. Next season he could be at Estadio Del Crown against his superior namesake. Madness.— Callum Gibson (@gibby9790) March 18, 2018
Is anyone else still puzzled by the decision of Chris Coleman joining Sunderland?? Just shows what you can do when you don’t have Gareth Bale I suppose!!— Neil Young (@neilyoungster) March 18, 2018
It could all be bombast at this stage but Chris Coleman saying he'll stay at #SAFC, regardless of what division the club is in, is exactly the commitment that is needed from the manager and plenty more. Or he's a certifiable lunatic. One of the two.— Chris Weatherspoon (@christoph_21) March 16, 2018