Just 12 months after seeing their top-flight dream evaporate inside the clammy atmosphere of a Millennium Stadium whose retractable roof had been closed before kick-off, United were contemplating life in the third tier for the first time in their history.
It was the ultimate play-offs hangover and one that took a further three years to truly shake off.
No-one is suggesting such a fate awaits Leeds this time around. The club has come a long way since the summer of 2006, when the Premier League parachute payments following relegation had just dried up and an ageing squad that always seemed to have one crack at winning promotion and one crack only under Kevin Blackwell, suddenly started to creak.
Nevertheless, there is more than a whiff of the unknown in terms of how the Elland Road club will fare in the coming weeks and months.
Bielsa, for his part, is adamant the strides taken by United in his first year at the helm must be built upon.
“One of the things is to improve, with illusion, the things we made last season,” said the Leeds chief during a pre-season that has taken his squad from York to Sardinia and back to Thorp Arch via a week Down Under.
“If we can improve what we made last season, obviously we can arrive at the goal we want to achieve.
“The last season, our idea and our goal, was promotion. But, finally, we did not get (there). Obviously, everyone was disappointed but now we renew this option.
“Hopefully, we will do that but the most important (thing) is we are in the condition needed to finally achieve.”
The good news for those who make the fortnightly pilgrimage to LS11 is that Bielsa remains in residence.
For a few days in the immediate aftermath of the play-off defeat to Derby County, this seemed in doubt only for Leeds heartbeats to calm after the Argentinian confirmed he wanted a second tilt at leading the club into the Premier League after all.
For Adam Forshaw, the news that Bielsa was sticking around brought a timely lift at a time when the pain of that aggregate loss to the Rams was still very raw.
“Continuity is a big thing,” said the midfielder ahead of Sunday’s trip to Bristol City. “He (Bielsa) knows what he wants from us and we know what he wants from us.
“We have gained a lot of experience, and we are now a lot more aware about how the manager and the staff want us to play. We are a lot more accustomed to it, if you like.
“I think if we can just go that one step further, try and gain a little bit more fitness and play with the intensity that we did last season, then I think we will be a force to be reckoned with.”
The close season began with suggestions from within Elland Road that the target was four high quality loans, including the return of Jack Harrison, during a summer that would have to yield at least one significant sale to keep the club within Financial Fair Play parameters.
Jack Clarke’s subsequent move to Tottenham Hotspur for an initial £10m seemed to tick the latter box, while Helder Costa’s arrival from Wolverhampton Wanderers more than satisfied the “high quality” threshold laid down for loanees.
The immediate return on loan of Clarke was also welcome but, since then, United’s recruitment has brought more questions than answers.
Pontus Jansson’s surprise departure divided supporters, not least because it broke up a partnership that opposition teams found so tough to break down that both the Swede and Liam Cooper were named in the PFA Championship Team of the Year.
As it stands with the closing of the transfer window just a week away, Ben White – the loanee from Brighton & Hove Albion who is yet to play at a higher level than League One – seems Cooper’s most likely partner. Judging by the final pre-season friendly against Serie A side Cagliari, this could be a big risk in a league as unforgiving as the Championship.
Still, if anyone can make this work then it is Bielsa. His first year in England proved as much, the response to an ever lengthening injury list being merely to pluck an understudy from the Under-23s.
Clarke emerged via this route, as did the hugely talented Jamie Shackleton. If similar gems are lurking in the United Academy then Bielsa is the man to provide a platform to showcase that potential.
Forshaw agrees, adding: “I think one thing the manager has done that is exceptional is with the young players that he has brought through.
“The future is so bright. I have never been at a club with so many good young players.”
Bielsa opting to stay means he will this Sunday become the first manager to start back-to-back seasons at Elland Road since Simon Grayson.
This constant chopping and changing since 2012 is an indication of the instability that has dogged Leeds in recent years. The hope now, however, is that Bielsa staying together with the burning desire among the players to banish the memory of May’s play-off heartache will be enough to inspire another concerted push for the Premier League.
“It has been very hard,” admitted defender Gaetano Berardi, red carded in that second-leg collapse against Frank Lampard’s Rams.
“Because when we left the last game against Derby we all had difficult weeks. But then we had to forget the last game. I think everything was gone when we started pre-season.
“The motivation is still there because we lost a good chance last year but I think we know we can try again.
“We have all the skills we need to try. The confidence is very high.”
Ins: Jack Harrison (Manchester City, loan), Ben White (Brighton & Hove Albion, loan), Jack Clarke (Tottenham Hotspur, loan), Helder Costa (Wolverhampton Wanderers, loan).
Outs: Jack Clarke (Tottenham Hotspur, £11.5m), Pontus Jansson (£5.5m, Brentford), Samuel Saiz (Girona, £2.5m), Caleb Ekuban (Trabzonspor), Paudie O’Connor (Bradford City), Aapo Halme (Barnsley), Mallik Wilks (Barnsley), Liam Kitching (Forest Green Rovers), Tyler Denton (Stevenage), Sam Dalby (Watford), Hadi Sacko (Denizlispor), Oriol Rey (Real Valladolid), Hugo Diaz (Getafe), Jay-Roy Grot (Vitesse Arnhem, loan), Lewie Coyle (Fleetwood Town, loan).
Verdict: With a week to go until the transfer window closes, Leeds United’s squad looks to be a couple of players short. Marcelo Bielsa’s options at centre half and centre forward look thin, just as they did last season. And we all know how that panned out, as a scintillating start gave way to a finale where his players gave every impression of suffering from burnout. Long-term followers of Bielsa’s career will not have been surprised, the hugely demanding playing style espoused by the Argentinian having brought similar campaigns at the helm of Athletic Bilbao and Marseille. Bielsa, of course, bristles at the suggestion his sides wilt during the second half of a season so expect no let-up in the demands placed on his players. Without further additions - especially with Kemar Roofe, into the final 12 months of his contract, possibly heading out before the deadline - a similar season seems to lay in store.
Prediction: Top-six finish.