Sunderland reached the FA Cup fifth round for the first time since 2015 as Habib Diarra's contentious first-half penalty earned a 1-0 win away to Oxford United.
The Championship side proved stubborn opponents on a pitch that had been lashed by rain earlier in the day, but the surface held out at the Kassam Stadium and so did Regis Le Bris' Premier League visitors, scraping through thanks to a decision that convinced few supporters in the home section.
Dennis Cirkin was the beneficiary, going over in the box under a challenge by Christ Makosso. With no VAR to advise, one look was all referee Thomas Kirk got and Diarra capitalised to help his team emerge from a tricky tie.
"We're not getting any decisions at the minute," Oxford boss Matt Bloomfield. "That's factual. There's been many wrong decisions against us recently."
Asked whether he felt it was a correct call to penalise Makosso for the penalty, Sunderland boss Regis Le Bris said: "I didn't review the situation. We need to trust the referee."
This had been a league fixture last season, Sunderland losing 2-0 here in April en route to ending the regular campaign with five straight defeats. Four weeks later they triumphed in the play-off final at Wembley to secure their top-flight return and have not looked back.
Oxford by contrast are facing the real prospect of their time in the second tier ending after two seasons, but they put relegation fears aside and put up a worthy fight, particularly in the closing stages as the Wearsiders were made to cling on.
It had looked like being a straightforward afternoon for Sunderland, who were the better team in the first half. After 13 minutes, Chemsdine Talbi crossed for Wilson Isidor, who missed his kick with his first effort, then shovelled his next into the side-netting.
Jamie Donley, whose audacious long-range lob gave Leyton Orient the lead against Manchester City in the fourth round a year ago, albeit via an own goal from the goalkeeper, had Oxford's first sight of goal when his drive was beaten away by Robin Roefs. The 21-year-old on loan from Tottenham was making only his second appearance after getting injured on his debut in the previous round.
Oxford had not been awarded a penalty since their League One play-off semi-final against Peterborough 85 games ago.
Sunderland were under no such curse and went ahead after 33 minutes. Makosso went in clumsily and tripped Cirkin inside the box, and, although the decision appeared generous towards the Premier League side, Diarra stepped up to calmly send the goalkeeper the wrong way.
Makosso came as close as anyone in yellow at the end of the half with a header wide from Will Vaulks' throw-in.
At the break, boos greeted the officials from home supporters who felt that decisions - the penalty chief among them - had gone against their side.
Matt Ingram's saves kept Oxford in with a shout as the tie entered its final half-hour, first from Romaine Mundle's drive, then acrobatically from a long-range blast from Talbi. Trai Hume was also denied at the goalkeeper's near post from outside the box.
Oxford's moment looked to have arrived in the 70th minute when the ball dropped in the box for substitute Jamie McDonnell, but he could only side-foot his effort over the bar.
