It is the most dreaded piece of alliteration in the football lexicon, but one that teams would be foolish to overlook. Second season syndrome has snared many an overconfident side who have been deluded into thinking that one year of survival guarantees them a permanent place at the top table.
Last season was the first time in seven years that all three promoted teams survived their first season in the top flight. But the new battle began as soon as the last one ended. All three have work to do to ensure that last season was not just an anomaly.
Here we assess each of the three teams' chances of surviving the dreaded drop for a second consecutive year.
It's difficult to know if Rafa Benitez is naive or if he just really loves Newcastle, because a lesser man would have resigned by now. He must have had his suspicions when Mike Ashley promised him "every penny generated by the club". It was that vow which kept him at St. James' Park, but once again it seems that the Spaniard is being taken for a ride.
Newcastle have received more money in sales than they've spent on players so far this summer, which is both a shocking indictment of Ashley's spending and a testament to Benitez's eye for a bargain. Particularly impressive was the £3m signing of experienced Swiss international Fabian Schar. But anything more expensive will require players to be sold first.
The key to avoiding second season syndrome is often making minor alterations, changing things up without affecting the overall balance of the team. Given his limited budget, Benitez can't change things on the personnel front as much as he'd like, so it falls to him to make modifications to his tactical setup instead.
Newcastle need to become better at breaking teams down when they go behind. They suffered ten 1-0 defeats last season - more than any other Premier League side - because they lacked the ability and in some cases the ambition to chase a game. Ayoze Perez, despite his improvement, isn't good enough to carry the goals burden by himself.
Some things are beyond the manager's control. The fitness of Jamaal Lascelles will be imperative, as Newcastle's defence was significantly leakier last season in the few games when he was absent. Jonjo Shelvey must continue last season's form into the new campaign, and maintain the new-found discipline that Benitez has instilled in him.
But the squad is paper-thin, and with no further funds incoming, Benitez will be crossing his fingers for an injury-free season. Anything else could spell crisis for Newcastle.
Verdict: Without Rafa they'd be in real trouble. His influence should be enough to keep them afloat, but only just.
Brighton & Hove Albion
If Newcastle are crossing stormy seas, Brighton is the picture of calm. Few clubs were as united for the duration of the 2017/18 season as the Seagulls, for whom a late season slump in form disguised the fact that they were pretty much safe as early as March.
Maintaining that state of harmony will be integral to Brighton's continued survival, but they can't just rely on last season's stars. Pascal Gross' debut season will take some repeating and Glenn Murray, who will be 35 in September, can't be expected to score so many important goals again.
Hughton will look to Jurgen Locadia, signed from PSV Eindhoven in January, and to new arrivals Florin Andone and Alireza Jahanbakhsh to ease the burden on Murray's shoulders. Malian international midfielder Yves Bissouma will provide more competition for the midfield, and Nigerian World Cup star Leon Balogun will do the same in defence.
To avoid second season syndrome, Brighton need to remember what made their first year such a success and build from there. Changes must be made, but if it ain't broke, don't fix it. The arrival of Bissouma for a club record fee would suggest that he will slot right into the team, but Hughton should be careful about breaking up the pairing of Dale Stephens and Davy Propper.
The same is true of the defence. One imagines that Balogun would not have joined the club if he was going to sit on the bench, but surely Chris Hughton will not separate the formidable partnership of Lewis Dunk and Shane Duffy? Maintaining the harmonious atmosphere will be more difficult with a bigger squad and so many players demanding game time.
What Brighton have going for them is their ability to employ different styles of football, which prevents them from becoming predictable. At times last season they played some fabulous football, most notably in a 4-1 demolition of Swansea. But in the win over Manchester United which secured safety, it was defensive solidity that triumphed.
Verdict: As long as Brighton keep mixing it up, both in terms of personnel and playing style, they should not find second season syndrome a problem.
Huddersfield getting relegated wouldn't be so much the result of second season syndrome as the resumption of footballing normality. The Terriers performed a miracle by surviving last season but with three ambitious new teams in the league, it will be even harder this year.
David Wagner, ever the sensible one, made keeping his squad together the top priority this summer. Jonas Lossl, Florent Hadergjonaj and Terence Kongolo, all key men during last season's run-in, have made their loan moves permanent.
Huddersfield need to score more than the league low 28 they managed last season, but their limited transfer budget makes it difficult to sign game-changing players. Ramadan Sobhi and Adama Diakhaby have been signed to solve the Terriers' goalscoring problems, but they scored just six goals between them last season. At least one of them needs to hit the ground running.
It was Huddersfield's defensive record which got them over the line last season and their solidity will be imperative again. Christopher Schindler was named the club's player of the season after leading his defence to 10 clean sheets, a number only bettered by the top seven. Huddersfield lost just one game in which they scored first in 2017/18.
The key to Huddersfield's survival will be how well they can learn from last season's failings. The Terriers struggled to stay in games after going behind, often losing by heavy margins as a result. They also had trouble breaking down opponents, most notably failing to find the net against Swansea despite playing 80 minutes against ten men.
Huddersfield lack the element of surprise that allowed them to shoot out of the gates 12 months ago. seven points from their first three games proved decisive, but by the end of the season they were on their last legs, producing heroic but draining performances in draws at Manchester City and Chelsea. Can the Terriers keep that up for a whole season?
Verdict: Will lightning strike twice? Surely not...Wagner will keep them in the mix until the end but it's likely to be in vain.