It was just a shame that so few were there to see it, with Saints’ ground half empty and an entire stand shu. The stay-aways looked to have made the right decision, however, as an hour desperately short on quality ticked painfully by.
But in the 66th minute Boufal, the £21m summer signing from Lille, scored a fabulous winner to pile on the misery for Sunderland.
To add to their problems the Black Cats, whose only two wins all season have come in this competition, had manager David Moyes sent to the stands after they were denied a late penalty.
Sunderland managed the first shot on target midway through the first-half with their first meaningful attack, Wahbi Khazri forcing a near-post save from Alex McCarthy with an angled drive.
Luckless Saints striker Jay Rodriguez, dogged by injuries for two years, was forced off after 25 minutes having failed to shake off the effects of a nasty clash of heads with Sunderland full-back Billy Jones.
With the prospect of extra time beginning to loom large Boufal finally broke the deadlock with the first bit of quality of the night. The 23-year-old controlled an up-and-under from James Ward-Prowse superbly, stepped around Jones, looked up and curled an unstoppable shot over the diving Pickford.
Moyes sent on Jermain Defoe in a bid to salvage the tie and the four-goal striker scampered through on goal with 10 minutes left but fired his shot too close to McCarthy.
Moyes’ frustration boiled over in stoppage time when no penalty was given after Anichebe went down.
McCarthy, Yoshida, Fonte, Stephens, McQueen, Reed (Clasie 82), Ward-Prowse, Hojbjerg, Boufal, Rodriguez (Olomola 26), Isgrove (Redmond 72).
Pickford, Jones, Kone, Djilobodji, Van Aanholt, Rodwell, McNair (Pienaar 87), Ndong ,Watmore (Gooch 87), Anichebe, Khazri (Defoe 72).