Sunderland fans have got used to watching some dross this season, with David Moyes' side having battled against the drop all campaign.
But this display topped the lot. This was supposed to be a derby, yet Sunderland produced their worst display under Moyes to date.
They were bright in the opening five minutes or so, winning three quick corners and ended the first half with more possession having regained some sort of control.
But the long spell in between was among the worst witnessed this season. And the bar has been low, very low, since the season kicked off in August.
Very few players came out of the game with any credit.
Jordan Pickford kept the Boro forwards at bay with some important first half saves but even he won't have been happy with Marten de Roon's opener.
Billy Jones and John O'Shea even less so. It was woeful defending, especially so early in the game. Sunderland all at sea.
The away end, so loud and proud before kick-off instantly deflated. This, after all, was against a Boro side that had gone 16 games without a win before Wednesday night.
You have to go all the way back to mid-December for the last time Boro won in the Premier League, against Swansea. Even Sunderland had won since then.
And Steve Agnew's side are also the lowest scorers in the top flight. Yet, the Sunderland defence just let them ease their way in front.
It took until the 21st minute for the first chant of 'We Want Moyesy Out'. It didn't last long but long enough for the Sunderland fans to have made their point. Again.
Second half the chants against the manager were more sustained.
Tellingly, this was the away support. Once the away support turn you know you are under pressure.
David Moyes, who patrolled his technical area all night, coming under increasing pressure from the fans.
The sold-out away following of 2,989 fans then got behind their team with the sold-out away end in fine voice during the second half - which saw a slight improvement.
That isn't saying much, mind, given how low the bar was set in the first half. Sunderland tried to rally but Brad Guzan wasn't tested anywhere near enough.
Sunderland were pedestrian in their build-up, Boro allowed to get men behind the ball.
The game was a more even-contest second half but Sunderland rarely threatened.
They are going down with a whimper. At one stage, Sunderland fans chanted: "Down with the Sunderland' towards the South Stand at the Riverside.
In response, Boro chanted "Down with the Boro." This season has reached the gallows humour stage.
In the end it was comfortable for Boro. Too comfortable by half. Sunderland made them look like one of the form teams of the division. Another grim chapter in this sorry season.
As the second half wore on, angry fans vented their anger again in Moyes' direction.
At the end of the game, the players were hit with chants of "You're not fit to wear the shirt."
"Championship football, it's on its way back...." sang the Sunderland faithful as the game edged towards an inevitable conclusion.
"We Want Moyesy Out" got another run out, this time louder and more intense along with Roy Keane chants and a rendition of "Are you watching Ellis Short?"
Loud boos rang out at full-time as the dejected Sunderland players went over to applaud the away support. The fans gave them both barrels in response.
Khazri and Pickford among the few to be applauded.
Sunderland beaten. Down and out. Championship-bound. Just end the season now.