Paris Saint-Germain's bid to win a first Champions League crown remains on course but the French giants only just survived a bumpy ride against Aston Villa on Tuesday as old ghosts almost came back to haunt them.
Luis Enrique's side have won plaudits for the thrilling way they have played in recent months and went into the second leg of their quarterfinal on a run of one defeat in 30 matches.
That single loss came at home to Liverpool in the first leg of the last 16 and was overturned a week later at Anfield, before they beat Villa 3-1 at the Parc des Princes with an outstanding performance.
So when they found themselves 2-0 up before the half-hour mark in Birmingham on Tuesday, breakaway goals by full-backs Achraf Hakimi and Nuno Mendes putting them 5-1 ahead on aggregate, the tie seemed over with PSG cruising towards the last four.
Then they switched off, allowing their Premier League opponents to pull one back before halftime and then score two goals in three minutes early in the second half through John McGinn and Ezri Konsa.
With the visitors rocking, Villa needed only one more goal to force extra time, and they might have got it but for some big saves from PSG goalkeeper Gianluigi Donnarumma and a crucial late block by Willian Pacho.
"I think the intensity levels dropped when it got to 2-0. We need to cut out these little errors for the semifinals because you can pay a heavy price," captain Marquinhos told broadcaster Canal Plus.
The Brazilian knows that better than anyone.
At 30, he is the elder statesman of the youngest team left in this season's Champions League, and he has plenty of unhappy memories in the competition with the club he joined in 2013.
None could be more traumatic than the 6-1 defeat in Barcelona in 2017, which came after PSG had won 4-0 at home – Barca went into the 88th minute needing to score three goals, and did so as PSG collapsed.
The Paris coach that night was Unai Emery, with Luis Enrique on the Barcelona bench. Fast forward eight years and the two men were facing off again, with the latter now in charge of PSG.
"You can never be over-confident, because a football match can change in an instant," Luis Enrique acknowledged after Tuesday's game.
Whether it has been complacency or just nerves, PSG have had other disastrous collapses in Europe, including against Manchester United in 2019 and Real Madrid in 2022.
FOUR SEMIS IN SIX YEARS
The difference this time is that they held on to go through, and can now look forward to a semifinal against either Real Madrid or Arsenal.
"We can savour this because it is always difficult to get through to the Champions League semifinals. It is the second consecutive year and we are very happy," added Luis Enrique.
A year ago, PSG lost to Borussia Dortmund in the semis. Kylian Mbappe has since departed, but Luis Enrique has succeeded in making the Qatar-backed side stronger without him, Tuesday's second half notwithstanding.
"There were lots of doubts about the team but I think the team is even better than last year and we will fight for every trophy right to the end," said the coach.
This is PSG's fourth Champions League semifinal in six seasons, the only two years in which they failed to get to the last four in that time coming in 2022 and 2023.
Those were the years in which they had Lionel Messi alongside Neymar and Mbappe in attack.
The superstar approach did not deliver the success they hoped for, and the current side is undoubtedly more impressive.
They have not lost a domestic game since last May, have already clinched the Ligue 1 title and are through to the French Cup final.
However, PSG are still not finding it easy to make the step up in continental competitions.
Tuesday's defeat was their fifth in 14 Champions League matches this season, and their 10th loss in 26 games in Europe since the beginning of the last campaign.
Villa are the fourth Premier League team to beat PSG after Newcastle United, Arsenal and Liverpool. And Arsenal could be up again next.