For Newcastle United, a reaction to what happened at Barcelona, their heaviest ever European defeat.
For Sunderland, a reaction not necessarily to last week's Brighton defeat but certainly the loss that came before. Getting knocked out of the FA Cup to Port Vale was, admitted Regis Le Bris, "embarrassing".
For both, winning the derby would go a long way to easing the pain of what went before.
Here are the main talking points that will go a long way to deciding Sunday's game:
MIDFIELD BATTLE AND BRUNO'S PAIN
Bruno Guimaraes couldn't hide his anger and couldn't bite his tongue. Either that or didn't want to.
In the mixed zone immediately after Newcastle's December defeat to Sunderland, Bruno blasted his side's display.
"The whole message in the changing room today was do it for the fans and we didn't," he said.
"It's so embarrassing for me and frustrating because we know we have a better team than them. It's clear for me.
"But we didn't perform like a better team today. It makes me feel angry. I have to be very worried about my words because I'm very angry with the performance."
Three months have passed but how frustrated Bruno will be to not get the opportunity to put things right this weekend. The Brazilian will be missing for Sunday's game, and so might Sandro Tonali after he was forced off at Barcelona.
Does that hand the initiative to Sunderland in the midfield battle? Well Le Bris will at least be able to call on his first choice trio of Granit Xhaka, Noah Sadiki and Habib Diarra. What does Howe do if Tonali is out? Jacob Ramsey, Joe Willock and Joelinton? Surely this isn't the game to give the Nick Woltemade midfield experiment another run-out?
RECOMMENDED READING:
KEY FLANK
Sunderland are sweating on the fitness of some key stars ahead of Sunday's game, with Dan Ballard having been forced off in the Brighton defeat and Le Bris admitting he must decide whether to roll the dice with Nordi Mukiele.
If Ballard is unavailable, that might make Le Bris' mind up for him on Mukiele. The selection is likely to have an impact on how Sunderland's right side is made up.
If Ballard and Mukiele were both to play, that could mean the latter playing at right-back and Reinildo returning at left-back, with Trai Hume moving to the right side of midfield.
If neither are available, Luke O'Nien could come in at centre-half but Le Bris might still opt to play Hume further forward with Lutsharel Geertruida behind him.
Lewis Hall will take every opportunity to get forward and he'll have Anthony Gordon or Harvey Barnes in front of him on Newcastle's left.
Chris Rigg impressed in the absence of Bertrand Traore and Nilson Angulo on the right last week, but don't be surprised if the teenager drops out and Le Bris goes with Hume for extra protection.
NEWCASTLE VULNERABILITIES BUT CAN SUNDERLAND TAKE ADVANTAGE?
Newcastle are only four goals shy of conceding as many as they did in the entirety of the last Premier League campaign and still have eight games to play.
Their defensive vulnerabilities were exposed by Barcelona in quite brutal fashion in midweek, a reminder of an issue that badly needs addressing. The clean sheet at Chelsea last week was Newcastle's first shut-out since the win over PSV at the end of January. Domestically, the only two teams they've managed to keep out since the turn of the year are Crystal Palace and Wolves.
But will Sunderland pose enough of an attacking threat to take advantage? The Black Cats have scored just one non-penalty goal in their last six games, not helped by the fact they're missing a number of wide attackers.
Since the end of November, Sunderland have only scored more than a single goal in a game on two occasions, the home wins over Crystal Palace and Burnley.
PLAY LIKE LIVES DEPEND ON IT - BUT SUNDERLAND ALSO HAVE SOMETHING TO PROVE
The Newcastle fans had not long left the Nou Camp but Howe, in his post-match press conference, was quickly turning his attention to what comes next.
“Now, it’s all about Sunderland,” he said.
“It’s not about today. It’s about learning from today, evolving and changing if we need to. But it’s about the next game and making sure we’re mentally and physically ready for what’s going to be a huge game for us and the whole city.
"It’s huge. There’s no point talking about it though, we’ve just got to play. We’ve got to play like our lives depend on it.
“It’s such a big game for the city, for our supporters, for everyone connected with the club. We know that. We knew it before the first game and we know it even more now."
Newcastle's players were accused of not understanding what the derby means after their no-show at the Stadium of Light. Howe and the Magpies can't afford a repeat.
But Sunderland have something to prove to. That's always the case in this fixture, but Port Vale still stings a fortnight on. It'll be a long three weeks without a game for the Black Cats if Sunday doesn't go to plan.
THE STORY OF THE STRIKERS
Who plays up front for Newcastle? The fact that £125m duo Nick Woltemade and Yoane Wissa were unused substitutes at Barcelona was pretty telling, but then the same can be said of the fact a winger in Anthony Gordon and a fringe figure in Will Osula have been preferred in recent weeks.
Gordon was brilliant up-front at Chelsea last week but the England international really needs space behind to exploit. He's unlikely to get that against Sunderland. So does Howe tinker and recall Woltemade to give the German international the chance he'll be desperate for to attempt to make amends for his December own-goal?
As for Sunderland, it would be a major surprise if it wasn't Brian Brobbey leading the line. But Le Bris admitted last week the striker is still working his way back to full fitness after his recent injury. He'll be unlikely to last the full 90 minutes, which means Eliezer Mayenda or Wilson Isidor will almost certainly get an opportunity from the bench.
There's every chance Sunday's game will be cagey. One goal might win. Mayenda? Wissa? Isidor? Osula? Could a star substitute become a derby hero?