In the face of adversity Liverpool delivered.
Having made a habit of dishing out hidings at Anfield this season, this was a triumph of a very different kind.
Jurgen Klopp's men were far from their blistering best but, crucially, they dug deep to break Sunderland's stubborn resistance.
This was all about perseverance as Liverpool simply refused to be denied.
Class may have been in short supply but there was grit and determination aplenty.
Already without the injured duo of Daniel Sturridge and Adam Lallana, the Reds were stung by the sight of Philippe Coutinho departing on a stretcher before the break.
The little Brazilian left Anfield on crutches with his right ankle in a protective boot amid fears he's facing an extended spell on the sidelines.
In the absence of their magician, Liverpool's powers were severely depleted. They huffed and they puffed but they struggled to find a way past the David Moyes built defensive wall in front of them.
As the minutes ticked away feelings of anxiety and restlessness in the stands grew.
After Jordan Henderson over-hit a pass midway through the second half, Klopp sensed that the atmosphere was getting to his players.
The Reds boss took matters into his own hands. This was Klopp the conductor.
Throwing his arms up in dismay at what he perceived to be unwanted negativity around him, he turned and dished out the mother of all rollickings to the fans in the Main Stand.
It was a master stroke. The mood around Anfield was instantly transformed as supporters answered his rallying call.
Noise levels were cranked up and so was the pressure as Liverpool, inspired rather than inhibited by the soundtrack, started to turn the screw.
Something special was required to break the deadlock and with 15 minutes to go Divock Origi took centre stage.
It's been a hugely frustrating season for the young Belgian striker.
His opportunities have been limited and when he has featured he hasn't been able to hit the heights he was at back in the spring.
Origi was tormenting defenders before he was taken out of the Merseyside derby in April by Ramiro Funes Mori's X-rated challenge and suffered ankle ligament damage.
It's been a long way back. Without regular action, he's been unable to do himself justice.
Yet handed the chance to shine following Coutinho's early exit he grabbed it with both hands.
There appeared to be little danger when Origi collected Henderson's pass on the far side of the penalty box.
However, he darted away from Duncan Watmore and whipped an unstoppable right-footer beyond Jordan Pickford and into the far corner.
Anfield erupted. Relief spread like wildfire. Origi's first Premier League goal for seven months had turned a damaging setback into a cherished victory.
Belatedly, Moyes had to show a modicum of ambition and they were duly killed off on the counter late on when Sadio Mane raced away from Jason Denayer before being cynically upended by Didier Ndong. James Milner tucked away his fifth goal of the season from the penalty spot.
Steven Gerrard, watching on from the directors box, will have admired that never-say-die spirit. The Kop icon knows how far that can carry a side.
Moyes claimed in the build up that “anybody who plays against Liverpool has to park the double-decker bus” and there were no surprises with his game plan.
Top scorer Jermain Defoe was effectively forced into action as a second left-back as Sunderland got men behind the ball and rarely ventured out of their own half.
Despite enjoying 80 per cent possession in the first half, Klopp's men failed to make it count.
It was all too slow, too predictable. Denayer stuck to Coutinho like glue and prevented him from pulling the strings.
Nathaniel Clyne and Milner were playing so far forward they were effectively wingers but there was a lack of quality from the flanks.
Roberto Firmino and Gini Wijnaldum both forced saves from Pickford before the Reds suffered a scare at the other end.
Clyne was caught napping by Billy Jones' hopeful punt back into the penalty box. Steven Pienaar pounced but Loris Karius came out to make a crucial block and divert it behind.
If that was the best of Karius what followed was downright bizarre.
As the young German keeper attempted to play a goal kick square to Clyne, he inexplicably knocked it straight out for a corner. To his relief, the careless error wasn't punished.
Klopp stood on the touchline urging Liverpool to move the ball quicker.
Firmino skipped away from Patrick van Aanholt but blazed over.
Mane, who has done so much damage to visiting teams this season, was strangely subdued. The Senegal international got into some great positions but his touch let him down and he kept on taking the wrong option.
On the half hour mark came the body blow of losing Coutinho, who was caught by the studs of Ndong as the midfielder cleared.
The Brazil international immediately winced in agony as he hit the turf, clutched his right boot and signalled to the bench that his afternoon was over.
The midfield trio of Henderson, Emre Can and Gini Wijnaldum worked tirelessly to keep the Reds on the offensive but for so long their efforts were in vain.
Before the interval Dejan Lovren and Can both wasted headers. In the second half there was much greater urgency but Liverpool continued to lose their heads in the final third.
Mane scuffed tamely at Pickford before Milner was inches away from diverting home Wijnaldum's volley and Henderson curled a free-kick over.
For so long a spectator, Karius did well to save at the feet of Watmore after the Black Cats had briefly broken off the shackles. Liverpool now boast successive league clean sheets for the first time since March.
Denayer provided a goal saving block to deny Mane after a cute backheel from the impressive Lovren.
Urged on by the Kop, Liverpool redoubled their efforts and Origi was soon sliding on his knees in jubilation.
Firmino limped off after a kick from Lamine Kone which prompted Klopp to get involved in an angry exchange with Sunderland assistant boss Paul Bracewell.
When Mane was chopped down and Milner converted, Anfield could finally relax.
There was a brief Premier League debut for exciting Academy attacker Ben Woodburn in stoppage time as the Kop broke into a rendition of 'David Moyes is a football genius'.
An old foe scowled. He had been sent packing pointless once again.
Source: Liverpool Echo
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