Derbies can be strange things, games out of time that can often define seasons, particularly at those clubs for whom winning trophies feels an impossible dream.
The explosion of euphoria at Sunderland last Sunday as they beat Newcastle United 1-0 was extraordinary, all the more so given the contrast to the fury after the 4-0 loss to Aston Villa three weeks earlier, when half the crowd left by half time and those who remained were intent largely on expressing their displeasure.
Jermain Defoe, the scorer, was overwhelmed, leaving the pitch at half time in tears and breaking down again in his post-match interview. And he joined the club in January.
For those whose connection with the club stretches back longer, winning a record fifth derby in a row, the fifth in two years, emotions ran even higher.
Sunderland fans, who before the recent run had seen their team win only five league derbies in the previous 46 years, still relish each one.
The problem has been that at times they perhaps relish them too much, the expenditure of nervous tension leaving them drained. After the 1-0 win at St James' Park in December, Sunderland took one point from the following four Premier League games.
The two derby wins last season were followed by runs of one point from eight games and one win in eight.
After Paolo Di Canio led Sunderland to a 3-0 win at St James’ the previous season, they won one of their next 13 games.
When Roy Keane, in October 2008, became the first Sunderland manager to win a home derby in 28 years, it was followed by a run of six defeats in seven games that saw him sacked.
If that sort of post-derby collapse happens again, Sunderland will be relegated. For all the positivity last Sunday, they remain just three places and three points above the relegation zone – albeit with QPR and Aston Villa, two of the sides below them, having played a game more after their 3-3 draw on Tuesday.
In the game following each of the past three derby wins, Sunderland have faced Hull City.
They have lost all three, with Hull’s manager – and former Sunderland manager – Steve Bruce gaining some small measure of revenge.
At least it is not Hull again this Saturday, but Crystal Palace are in form.
They have won four of their past five games to move up to 11th, and also have a manager with Newcastle connections.
Perhaps the greatest stain on Alan Pardew’s record at St James’ was his part in the first four of those five derby defeats.
While Newcastle’s collapse since his departure at the turn of the year has led to some slight reassessment of his time at the club, his critics will always have that stick with which to beat him.
The danger of thinking the job is done is obvious enough that players talk openly about it.
“The season hasn’t finished and we have massive games coming up,” Defoe said. “It’s important that we just concentrate on the next game, be professional and win that.”
An awareness of the problem and a capacity to deal with it, though, are different things.
What must be of particular concern to Sunderland is the fact that despite dominating against Newcastle, it took a brilliant volley – by Defoe’s reckoning, one of the best two goals he has scored – to win it.
The side still has a fundamental lack of quality and creativity.
Perhaps the lack of confidence that has exacerbated those qualities will start to fade, but this has been a chastening season and morale must still be fragile.
The suspended Sebastian Larsson, whose set plays offer at least the possibility of a threat when all else is insipid, will be missed, although Adam Johnson, who is still under police investigation over reportedly engaging in sexual activity with a 15-year-old girl, may be fit enough to start.
But perhaps the greatest pressure comes from the fixture list. In the last week of the season, Sunderland must go to Arsenal and then Chelsea.
The game in hand they will have on that penultimate weekend is unlikely to be much comfort.
If they are to survive, Sunderland probably need seven points from the next five games.
They cannot afford another post-derby hangover.
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