How do you explain the two extremes that Sunderland have reached in the last week?
At Selhurst Park they looked so composed, so clinical, a team who have seen this situation before and knew exactly what they needed to do to get out of it.
Indeed that is how they looked for the first 25 minutes here.
There was no great penetration, but Sunderland looked as confident on the ball as they have done for some time. The centre-halves never looked rushed, Darron Gibson tidy on full debut, Didier Ndong and Adnan Januzaj adding some drive and thrust.
Fast forward 75 minutes and all eleven were stood hands on hips after conceding one of the most embarrassing goals you will see at the top level of this game.
Four or five had made no effort to track back, and those who were in defence let Shane Long twice receive the ball under no pressure whatsoever. The time he had to pick his spot and stroke home was farcical.
The first goal was crucial, in fairness, and the Black Cats were unlucky. Handball by Manolo Gabbiadini, unquestionably.
Taking the lead suited the Saints, whose front line is fleet-footed and enjoy playing on the counter. Year after year of playing in the relegation scrap leaves mental scars and you could see the confidence rapidly draining from the Sunderland players.
Just as happened to Crystal Palace last week, fear and pressure paralysed. The passing that had been largely on radar became rushed, the spring in the step replaced by lead.
The discipline and concentration in defence lapsed and like all good teams, Southampton ruthlessly punished it. Right on the stroke of half-time, the game was settled. Sunderland not quick to press, then caught asleep in the box. Gabbiadini found space to turn and from that point their never seemed to be any prospect of a stirring comeback.
Highs and lows are to be expected in the basement battle, and previous campaigns have taught us to try and maintain perspective even when the wounds are raw and the only emotion you can reach for his anger.
There was a lack of application in the last 20 minutes, however, that cannot be excused. Rarely has the Stadium been so empty in the closing stages of a game and that aptly summed up what was happening on the turf.
David Moyes was also right to point out that Sunderland got worse the more attacking substitutions he made, but Wahbi Khazri at least showed the bravery to try and make something happen when the ball came to him.
Just as last week was far from the end, neither is this.
Sunderland have been in worse positions, but today was a reminded that this side is not as confident and resilient as the Selhurst display suggested.