The glaring attention that has been trained on one elite Liverpool great turned to another on Anfield's latest disappointing night.
Mohamed Salah has come under fire for his poor form this season - and was relegated to the sidelines for the consecutive Premier League game as the Black Cats came to town on Wednesday.
But it was leader Virgil van Dijk, a unmatched defensive foundation as Liverpool have collected the complete set of major prizes, whose poor form became the focus during the draw.
Van Dijk, 34, and Salah, 33, both signed lucrative new two-year deals in the summer, with scarcely a Liverpool question asked at the prospect of handing contracts to a experienced stars much approaching the end of their careers than the start.
Truly, it was a reason for joy - but now there is no denying the brutal reality that performance has dipped concerningly for both.
Liverpool have been susceptible in defence ever since head coach Arne Slot and the club's transfer committee undertook a £450m summer overhaul that has not yet shown anything like its worth.
At the same time, Van Dijk has started to forfeit the sense of being untouchable he has possessed since his £75m switch from Southampton in January 2018.
Van Dijk has not been helped by center-back colleague Ibrahima Konate's dramatic dip, along with Milos Kerkez struggling to adapt at left-back. But the esteemed defender has also had significant difficulties, as proved by his desperate handball that gave away a penalty in the significant Champions League loss to PSV Eindhoven at Anfield.
It was captured in the 67th minute on Wednesday when Chemsdine Talbi gave Sunderland a well-earned lead, Van Dijk giving the ball away before standing off and averting his body on a 25-yard shot that struck him and floated out of the reach of goalkeeper Alisson.
For a defender of such undoubted greatness, Van Dijk has an unusual habit of turning away on the ball, sometimes to Liverpool's disadvantage.
Ill fortune at the finale, yes, but it was a situation Van Dijk provoked with his unusual failure to make a decisive move, Sunderland's Talbi taking advantage.
"Van Dijk surrenders possession and then he just retreats. It's the mistake. 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 commanding, but right now he's slipping up and doubting himself."
As with Salah, a player of Van Dijk's stature must not be dismissed after securing two Premier Leagues, the Champions League, the FA Cup and two EFL Cups in a stellar Liverpool career.
He has, though, looked a faded version of his usual dominant persona this season, with the poest ball recovery rate per game during his Liverpool career, while tackles and interceptions are also down on last season.
And, while leadership should not be Van Dijk's sole responsibility alone in a Liverpool team full of experience, it was missing here. No-one was motivating a team that once again looked bewildered to take control by the throat.
Van Dijk's subpar showing, which ended with him being used as the desperate measure of acting as an makeshift forward, was indicative of a deeply underwhelming Liverpool performance - which made Sunday's win at West Ham seem like the exception rather than the rule.
Slot kept faith with the side that ended a run of nine losses in 12 games at London Stadium, Salah once more starting on the sidelines.
The Egyptian was introduced at the start of the second half as the Kop pinned hopes on him for inspiration. It failed to materialize, with £125m Alexander Isak also ineffective after opening his account with his first league goal for Liverpool on Sunday.
Slot would have been under increased scrutiny had Florian Wirtz's 81st-minute shot not deflected in off Nordi Mukiele to set up what Liverpool hoped would be a thrilling finale.
Late drama came - but at the other end. Liverpool were only saved from humiliation 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 dribbled past keeper Alisson.
Slot and his struggling title-holders ultimately had to accept the point knowing it could have been worse, with Alisson blessed 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 slow, labored and short on invention. 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 significant praise for the Reds' struggles on Wednesday must be given to Sunderland, who are being rewarded for a summer of notable ambition in the transfer market, coupled with the superb management of Regis le Bris.
The Black Cats were positive, self-believing and dangerous.
Sunderland are now sixth in the Premier League with 23 points. It is symptomatic 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.