Exactly what is the Manchester United rebuild going to cost?

How on earth did it come to this? Manchester United have been dumped out of the Champions League after an embarrassing attempt to negotiate one of the most favourable group draws imaginable.

A club who have committed over £300 million on transfer fees alone in the past two years have got exactly what they deserved. They had two cracks at qualifying, first at home to PSV a fortnight ago, then on Tuesday against Wolfsburg. But on both occasions they contrived to throw away the opportunity.

United cannot put this down to luck. Given the chance to grab the initiative in games, they haven't taken it. With an early 1-0 lead in Wolfsburg, they held their own for less than four minutes. And then, when they grabbed a second-half equaliser which momentarily appeared to have let them off the hook, fewer than 90 seconds went by before the home side struck again.

The narrative of United's season so far could have been summed up by the state of their line-up by full-time. Matteo Darmian limped off before half-time to be replaced by 18-year-old Cameron Borthwick-Jackson, joining fellow rookie Guillermo Varela in the full-back department. Later, Nick Powell would be thrown on up front with just two reserve appearances in a year after a knee injury under his belt and United would finish with an injured Chris Smalling going through the motions as a striker.

Is this what £300m buys you?

Van Gaal and executive vice-chairman Ed Woodward have been given a long leash in the transfer market but have so far delivered an uninspiring style of play and a squad which always looks two injuries away from a mini-crisis. They have certainly had a slice of bad luck in the infirmary but that is surely why you should be stocking your squad with strength in depth when you have such vast resources available.

The Dutchman has explained away the decision to trim numbers and bring down the average age, but there has been nothing but misery for United fans for most of the season so far.

United scored a grand total of seven goals in their Champions League group campaign, the same number that they netted in the two-legged play-off against Club Brugge. One fewer than Real Madrid scored in a single game against Malmo on Tuesday. Cristiano Ronaldo alone hit 11 in his six group-stage appearances.

And all that despite consistently bossing possession. Van Gaal calls it "dominating the game", fans call it boring and demand a greater attacking verve. Left with a must-win game in Wolfsburg, they caused the Germans trouble but looked likely to concede at any moment. Had they showed half of the same the decisiveness against PSV at Old Trafford, they would likely have been home and hosed before even stepping on the plane this week.

It was the first thing that came into Marouane Fellaini's mind when he was quizzed by BT Sport after the match on Tuesday. "We're disappointed but we have to look back. We should have beaten PSV," said the midfielder. "We created a lot of chances today, we should win as well but they scored three goals from set-pieces."

The size of this failure cannot be understated. There have been concerns raised relating to individual players for much of the season, whether it be Wayne Rooney, Memphis Depay, Fellaini, Bastian Schweinsteiger or Anthony Martial, but the truth is that it runs much deeper than that.

Rio Ferdinand was particularly scathing of United after the loss on Tuesday.

"It's embarrassing," the former United captain told BT Sport. "If you strip it back and look at this squad, this squad needs a real hard looking-at. There's no pace in the squad, no power, there doesn't seem to be great resilience at times. Them leaders you look for in situations like this, at the moment it looks like people are looking around at each other rather than being the man to stand up and saying 'I'm going to drag you through the forces'."

United have been telling anybody who will listen that Van Gaal is the man for them, perhaps even beyond his 2017 retirement date, but surely nothing short of the Premier League title can now secure him the hot-seat for a third term beyond the summer.

A spate of injuries, a manager at odds with the fans, a transfer policy which seems to be getting them nowhere and a string of dull performances that have earned them the indifferent results they have deserved... Manchester United are in a dire state.

They are rightly out of the Champions League and their season now stands on a knife-edge. If £300m gets you this, then what does a proper rebuild cost?