Norwich 0 Sunderland 3: Allardyce got tactics and subs spot on plus five other things learned from key win
It was a pulsating, passionate and feisty affair at Carrow Road - and that was just on the touchline
On the pitch, Sunderland's hopes of prolonging their stay in the Premier League were given a significant shot in the arm with the 3-0 win in Norfolk.
Here's what we learned:
Sunderland find the perfect balance. Finally.
Resolute and dogged at the back, clinical up front. Sunderland were on the ropes in the early stages.
But they weathered the storm, through a mix of good fortune and determined defending.
Sunderland then showed their teeth, Fabio Borini brilliantly executing his penalty before Jermain Defoe and Duncan Watmore added to the scoreline.
Keeping clean sheets has been Sam Allardyce's biggest bug bear. He was delighted with this one and more so his side's finishing.
Sunderland scored with all three shots on target in the match.
Allardyce got his subs spot on.
Big Sam has taken some stick in recent months about his choice - and timing - of substitutions.
But in Norfolk, he got it spot on.
Wahbi Khazri was poor again so it was no surprise to see him hauled off at the break, Watmore made a huge difference with his energy and running down the right-hand side.
He provided an outlet for Sunderland and got his rewards with the goal.
Seb Larsson made an impact too, setting up Watmore for his goal, while John O'Shea helped shore up the midfield late on.
Lee Cattermole was outstanding in central midfield.
As the fans waited the arrival of both teams at Carrow Road, the camera was fixed on the the players in the tunnel.
Cattermole had a steely, determined expression on his face. The most focused man in Norfolk, Cattermole excelled.
Sunderland's most creative player first half, he resorted to helping ensure the Black Cats went home with all three points with some crucial clearances.
Man of the match, Sunderland's skipper led from the front, running 11.68km.
Jan Kirchoff was excellent alongside him, he made five tackles, won possession nine times and made 40 passes - all team-high totals.
Thankfully Allardyce opted against changing his side and formation.
Despite strong rumours Allardyce was going to name Seb Larsson and Dame N'Doye in his starting line-up, Sunderland again named an unchanged side.
It meant they had named an unchanged starting line-up in three consecutive Premier League games for first time since May 2014.
Allardyce admitted afterwards he had almost opted to change both the side and formation.
Thank goodness he didn't.
Khazri aside, the team performed well as a unit on their way to a deserved win, their first league win at Carrow Road since March 1985, having gone 10 games without one.
Sunderland's fate firmly in their own hands - and goal difference could be crucial.
The game was littered with errors.
But come the final whistle it was Sunderland that had proved they could best cope with the mounting pressure.
Having closed the gap to just a single point, Sunderland still have their game in hand.
And the vastly superior goal difference of minus 18 compared to Norwich City's minus 25 could yet prove crucial.
Sunderland are deadly from the spot.
If it is one thing Sunderland are good at, it is taking a penalty.
When Fabio Borini was fouled for the 40th minute spot kick there was no doubt his strike wouldn't be about to hit the back of the net.
Why? Well, Sunderland have scored each of their last 17 pens in the Premier League, not missing one in the competition since December 2011.
An incredible record.