The intense focus that has been trained on one global Liverpool legend turned to another on Anfield's fresh desperate night.
Mohamed Salah has come under fire for his subpar performances this season - and was relegated to the bench for the second successive Premier League game as the Black Cats arrived on Wednesday.
But it was leader Virgil van Dijk, a peerless defensive bedrock as Liverpool have secured the complete set of top honors, whose dip in performance took center stage during the draw.
Van Dijk, 34, and Salah, 33, both agreed to new lucrative two-year deals in the summer, with scarcely a Liverpool eyebrow raised at the notion of offering extensions to a veteran duo much nearer to the end of their careers than the start.
Truly, it was a cause of celebration - but now there is no avoiding the harsh truth that standards have dropped alarmingly for both.
Liverpool have been vulnerable in defence ever since head coach Arne Slot and the club's scouting department embarked on a £450m summer overhaul that has not yet shown anything like its worth.
Simultaneously, Van Dijk has started to lose the aura of invulnerability he has possessed since his £75m move from Southampton in January 2018.
Van Dijk has received little support by fellow defender Ibrahima Konate's collapse in form, along with Milos Kerkez failing to settle at left-back. But the esteemed defender has also fought his own battles, as highlighted by his panic-stricken handball that gave away a penalty in the heavy Champions League loss to PSV Eindhoven at Anfield.
It was exemplified in the 67th minute on Wednesday when Chemsdine Talbi gave Sunderland a deserved lead, Van Dijk surrendering the ball before retreating and averting his body on a 25-yard shot that struck him and looped out of the reach of goalkeeper Alisson.
For a defender of such undoubted greatness, Van Dijk has an peculiar tendency of shying away on the ball, sometimes to Liverpool's detriment.
Misfortune at the finale, yes, but it was a situation Van Dijk invited with his atypical failure to take charge, Sunderland's Talbi taking advantage.
"Van Dijk loses the ball and then he just retreats. It's the wrong decision. He needs to go to the ball. Him not making the decision means that no one else knows what to do."
"Virgil Van Dijk last season couldn't make a mistake. Every game he was dominant, but right now he's making mistakes and second-guessing himself."
As with Salah, a player of Van Dijk's pedigree must not be written off after winning two Premier Leagues, the Champions League, the FA Cup and two EFL Cups in a illustrious Liverpool career.
He has, though, looked a pale imitation of his usual dominant persona this season, with the poest ball recovery rate per game during his Liverpool career, while key defensive stats are also down on last season.
And, while leadership should not be Van Dijk's sole responsibility alone in a Liverpool team packed with experience, it was missing here. No-one was rousing a team that once again looked clueless to grab the game by the scruff of the neck.
Van Dijk's subpar showing, which ended with him being used as the desperate measure of acting as an makeshift forward, was representative of a deeply underwhelming Liverpool performance - which made Sunday's win at West Ham seem like the exception rather than the norm.
Slot stayed with the side that ended a run of nine losses in 12 games at London Stadium, Salah once more observing from the sidelines.
The Egyptian emerged at the start of the second half as the Kop pinned hopes on him for inspiration. It was not forthcoming, with £125m Alexander Isak also anonymous after getting off the mark with his first league goal for Liverpool on Sunday.
Slot would have been under greater pressure had Florian Wirtz's 81st-minute shot not deflected in off Nordi Mukiele to set up what Liverpool hoped would be a grandstand finish.
Late drama came - but at the other end. Liverpool were only avoided defeat in stoppage time when Federico Chiesa's outstanding recovery run allowed him to turn Sunderland substitute Wilson Isidor's shot off the line after he had beaten keeper Alisson.
Slot and his struggling title-holders ultimately had to settle for a draw knowing it could have been worse, with Alisson fortunate to turn Trai Hume's shot onto the bar in the first half before Omar Alderete headed against the post after the interval.
Liverpool were sluggish, unimaginative and lacking in ideas. Even the typical final push after the equaliser carried scant belief. Showings like this are the reason their attempt to retain the title has fallen apart.
But huge credit for the Reds' struggles on Wednesday must be given to Sunderland, who are being seeing the results for a summer of notable ambition in the transfer market, coupled with the superb management of Regis le Bris.
The Black Cats were adventurous, assured and threatening.
Sunderland are now sixth in the Premier League with 23 points. It is indicative of the manner in which they have adapted to life in the Premier League that they will be frustrated they left Anfield without adding two more to their tally.
For Slot and Liverpool, it is back to the drawing board.