This was bad news for all the struggling clubs who had assumed Sunderland were certain to remain in the relegation spots – that assumption no longer looks safe. Gus Poyet is resurrecting a team that for most of the season has looked dead and buried.
Fittingly Sunderland's revival was confirmed by a freak occurrence – not another absurd blunder or ridiculous decision, two phenomena that have hampered Sunderland too often already in this campaign, but an Adam Johnson hat-trick of all things. If teams are to clamber out of danger, they need their major players to find form and Johnson did that against Fulham to spectacular effect. He had scored only one league goal this season before this showdown at Craven Cottage, where he scored three fine goals and created Sunderland's other one for Ki Sung-yueng.
"It was one of those days where you look back and think everything went for you," said Johnson. "I think everyone was writing us off but now there are going to be a few teams looking over their shoulders."
This was the sort of performance that Sunderland were hoping to see regularly when they splashed out £10m to take the then England international from Manchester City in 2012. But the player failed to find consistency under Martin O'Neill and Paolo Di Canio and initially fared little better under Poyet, who eventually dropped him. Johnson had started only one of six league matches before his heroics at Fulham, although his displays when he did appear in recent weeks had suggested he was beginning to rediscover his best.
"Every player will tell you there are times when things just don't go for you," says Johnson. "You are still trying the same things I was trying [against Fulham] but they just don't come off for you. You take one extra touch. But just because players lose form, you don't turn into a bad player overnight. It's just one of those things and hopefully now it's a new year, new start. I just said to myself: 'Let's get back to my old ways.' Self-consciously I said: 'This is a new year, everything else has gone.'"
It is no coincidence that Johnson is coming good as he and his team-mates become more comfortable with the possession-based style Poyet has fostered since he replaced Di Canio three months ago. That is proving especially effective away from home, where Sunderland have won two and drawn three of their last five matches, counterattacking well in each.
"Johno has characteristics that mean he needs to be playing for a team that keeps the ball, passes it and gives him the ball at the right time," says Poyet, who explains that maximising the return from Johnson has been one of his aims since being appointed. "We were trying but it wasn't easy. We put him on the right in the beginning but we were not passing the ball well. Then we put him on the left to try to deliver and we were passing it better. In the last two or three weeks it was working better, the team was more solid and that gave Johno the freedom to go and perform."
Johnson's task now is to keep repeating such performances, especially at home, where Sunderland are without a league win since early November. If he manages to do so, not only could he help Sunderland avoid relegation but he may also achieve something that seemed equally improbable only a few weeks ago: earn selection for England's World Cup squad.
He won the last of his 12 caps in August 2012 but he dreams of going to Brazil and knows that his improvement, and Theo Walcott's unfortunate injury, make that possible. "In the last few weeks and months I felt like the door was almost closed on me but now I think if I keep playing like this you never know, I might make a late shout for the plane," he says.
"Theo is a good friend of mine. I have come through the under-19s and under-21s with him. You never want to see that [injury], I was gutted for him, but if you can gain off someone else's misfortune, you have got to try and take it. But I won't be the only one who is thinking about that. There are probably four or five good wingers who won't make the plane."
As for Fulham, too many of their major players were bypassed against Sunderland. Dimitar Berbatov and the returning Clint Dempsey offered little. And whatever positive things their veterans produced, such as Steve Sidwell's headed goal from a Damien Duff corner, were more than negated by bad defending. That is a recurring theme for them this season and the reason why they cannot pull away from the danger zone. Their manager Rene Meulensteen is counting on Brede Hangeland regaining his best form immediately when the Norwegian returns from a three-month injury lay-off in Tuesday's FA Cup replay against Norwich.
Man of the match Adam Johnson (Sunderland)