WELCOME to the Premier League, Louis! Now he knows how much he has to do to bring Manchester United back up to pace after Old Trafford's lost season under David Moyes.
Van Gaal looked apoplectic after losing to Swansea and decidedly unsettled by the fact that the same players who could hardly kick a ball in the right direction for Moyes couldn't handle the opening day under another new manager.
He spoke about the expectation levels at Old Trafford and the fact that some of his players clearly couldn't cope with it.
This may be news to van Gaal but not to the rest of us. I'm sure Moyes would have a few interesting things to say if the Dutchman was minded to ring him. It wouldn't be a bad plan. He'll need all the help he can get.
The reality of life in the Premier League is that Swansea won't be the only mid-ranking to lower level team fancying their chances against Manchester United.
Over the next six weeks or so, van Gaal will come face to face with many of the teams likely to be struggling at the bottom of the table. I'm sure Manchester United fans must have looked at an early season fixture list which including Swansea, Burnley, QPR, West Ham and mentally banked a lot of points, they must now be fearful.
The problem for van Gaal is that everyone else has been busy in the market this summer and so far, there has been no real sign of the kind of investment he badly needs to make.
He gave himself three months to put things right but on the basis of this performance, it might take three years.
I'm not sure what van Gaal can do to put things right in a short space of time. He wants to persist with a three-man defence which makes no sense to me when he clearly doesn't have the players he needs to do it.
He may have a poor enough defensive pool but it is one steeped in English football orthodoxy. Logically, 4-4-2 should be the way forward, at least until he can bring men to do the job he wants.
Oddly enough, I was leafing through Alex Ferguson's hugely controversial second book while I was watching this one and came across, his description of his last game in the first few pages - that wild 5-5 draw with West Brom in May 2013.
The words which stand out are; "Defensively, we were a shambles." That game was 15 months ago and it is clear that nothing has changed since.
Watching Liverpool against Southampton yesterday, it struck me forcibly how big a swing there has been between Anfield and Old Trafford in just 12 short months.
This time last year, Simon Mignolet made a fantastic save against Stoke City from a last gasp Jon Walters penalty and it proved to be the kind of moment which can help define a season.
Liverpool pushed forward from that point and over the nine months of the season, just got better and better. In the end, they lost their nerve.
But Rodgers has done some work in the transfer market to address weaknesses and two started against Southampton. Dejan Lovren looks more than capable and Javi Manquilo had a decent competitive debut.
I would have some qualms about the fact that Rodgers still hasn't addressed what I feel is a gap in central midfield. Stevie Gerrard is a great man to have pulling the strings from the half-way line when Liverpool are going forward but he is less effective when defence is needed.
And it was needed for a great deal of the game against Southampton. After Raheem Sterling put Liverpool in front early on, I sat back and relaxed and expected a bit of a party but I was badly wrong.
Southampton shrugged off a summer of upheaval and came roaring back at Liverpool. Nathaniel Clyne hit an equaliser, Shane Long missed a sitter and there were moments when I actually thought they could win.
It was good substitution which brought Ricky Lambert into the game and made the Saints think about his physical presence. He was in there battling with defenders when Daniel Sturridge won the game with a short-range toe poke.
Lambert's introduction wasn't quite a game changer but it came at the right time to unsettle defenders who just a few short months ago, trained with him on a daily basis.
Even after Sturridge fired them in front, Liverpool were hanging on but they won and banked three points. Rodgers has the luxury of a high performing season to lean on.
Of course, the elephant in the room for Rodgers was the fact that a certain Mr Luis Suarez is in Barcelona today playing football with a different shirt on.
For that reason, I'm sure Rodgers must have been really pleased to see Sterling and Sturridge both score and Lambert make an impact.
But it was impossible not to notice the big hole in Liverpool's game plan Suarez's absence creates. Rodgers must move heaven and earth to find a really good striker before the window slams shut.
The final game of the weekend was about Manchester City reasserting their power and they did that quite comfortably against Newcastle without ever really hitting their stride.
They won easily at St James Park as did Arsene Wenger and Arsenal at the Emirates on Saturday. Indeed, all the title aspirants had a good day. Manchester United and van Gaal stood out as the big losers.