Manchester United booked an FA Cup quarter-final with old rivals Liverpool at Old Trafford next month thanks to Casemiro's 89th-minute winner against Nottingham Forest.
The Brazilian dashed in to flick home Bruno Fernandes' free-kick, although the goal was only given after a lengthy Video Assistant Referee (VAR) check for a possible offside in the build-up.
On the ground where he famously won an FA Cup third-round tie to save his own job in 1990, Sir Alex Ferguson sat next to new United director Sir Dave Brailsford as under-pressure current boss Erik ten Hag preserved his only remaining chance of marking his second season with a trophy.
The visitors edged a game that did appear destined for extra time but wasted a string of excellent opportunities to break the deadlock.
Looking to reach the last eight for only the second time since 1996, Forest sparked only sporadically, with Divock Origi and Taiwo Awoniyi both having decent efforts saved by United keeper Andre Onana.
As it turned out, Casemiro's fifth goal of the season was enough to see them through.
But missing Harry Maguire with a suspected knee injury, United will have to be far more effective on Sunday when they visit Manchester City, who beat them in last season's FA Cup final.
"We lost one time in 2024. We are consistent," Ten Hag told BBC Match of the Day.
"It's not so easy when you have the whole backline and we have to shuffle and play players in different positions. I'm very proud we did it.
"Every win is important. We take it for 24 hours and then we move on. [We have] fantastic games coming up."
Ten Hag surprised a few people in his pre-match press conference when he said Antony was one of the quickest players over 10 yards and he had the stats to back it up.
Starting for the first time since his goalscoring contribution to the previous round's victory at Newport, it was not easy to see how he could arrive at that measurement.
The truth was the former Ajax man's possession tended to follow a pattern. Receiving the ball on the right, he would tend to take a couple of stuttering strides to his right, then either cut inside and go across the pitch for a few strides or simply lay the ball off.
It was not the reason United made Antony the club's second most expensive player in their history, behind Paul Pogba, when they paid £82m for him at Ten Hag's insistence just before the summer 2022 transfer deadline.
The Brazilian was unfortunate an early effort from the edge of the area flicked off the crossbar, the end of a well-worked corner routine and part of an early offensive that should have seen the visitors ahead.
Scott McTominay was in a far better position than he realised when, unmarked, he steered an eight-yard header straight at Forest keeper Matt Turner. McTominay did much better with another Diogo Dalot cross later in the half, stooping low to steer another header towards goal which Turner kept out with a smart reaction save.
Antony had one more effort on the Forest goal in the second half before he was replaced by Amad Diallo 17 minutes from time, looking thoroughly fed up as he trudged to the sideline.
Marcus Rashford was also having one of his more ineffective nights and when he blazed wide after darting into the box, it seemed certain the match was heading to extra time.
To the delight of the visiting fans, Casemiro had other ideas, with his first goal since September proving decisive.
Forest out but bigger challenges ahead
Compared to a relegation fight and a legal battle to avoid a points deduction they can ill afford, a midweek FA Cup fifth-round tie was very much third on the list of priorities for Forest owner Evangelos Marinakis, who watched on from his seat in the directors' box.
Manager Nuno Espirito Santo presided over a home victory over Manchester United in his early honeymoon period after replacing Steve Cooper.
Since then, two of their three victories came in FA Cup replays against lower league Blackpool and Bristol City and, worryingly, the venom appears to have gone out of their play.
Morgan Gibbs-White's best opportunity, when he forced a superb save out of Onana, turned out to be offside anyway. Origi worked hard but has never been the most reliable finisher, while Awoniyi wasn't his usual threat.
Once the weekend encounter at home to Liverpool is out of the way, Forest have a run of winnable fixtures that may determine their fate.
However, before that, at the beginning of next week, their legal battle begins to avoid a points deduction for breaking Premier League spending rules. The outcome of that could be pivotal to their top-flight survival fight.
Source: BBC
BDST: 0943 HRS, FEB 29, 2024
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