The absence of eight first-team players can't be overlooked at Manchester United at the moment, but the sight of Phil Jones and Juan Mata standing on the Old Trafford touchline waiting to come on against Chelsea in 2022 is the most damning indictment of the squad depth currently on show.
To give Mata and Jones the credit they deserve, they both influenced the game as substitutes for the final 11 minutes, a period when United finally got a grip of proceedings.
But on a night when Ralf Rangnick picked four teenagers on his bench, the sight of two 30-something players who will leave the club this summer waiting to come on wasn't lost on anybody. This wasn't a glimpse of the future but more akin to jumping in the DeLorean and rewinding to 2014.
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Rangnick rightly pointed out that the game was still in the balance when he made that double substitution and the quartet of Alvaro Fernandez, Hannibal Mejbri, Shola Shoretire and Alejandro Garnacho should get their chance during an easier run-in.
Seeing Jones and Mata come on was a reminder of the lack of squad depth within this group, however, an issue that is only going to be exacerbated this summer.
The challenge awaiting Erik ten Hag is to find a way to turn United into a team good enough to compete with Manchester City and Liverpool, but not only are the starting XIs at those clubs far superior to United, but they also have better options off the bench, especially for Jurgen Klopp at Anfield.
Of those eight players absent last night, three will leave this summer in Paul Pogba, Jesse Lingard and Edinson Cavani. A fourth, in Aaron Wan-Bissaka, has rarely looked good enough for United.
Harry Maguire, Luke Shaw, Fred and Jadon Sancho are the only players absent at the minute who are likely to be making a major impact next season and even for Maguire the jury may still be out.
With the injuries mounting, United still managed to name nine substitutes last night, but two of them were goalkeepers. At least one of Dean Henderson and Tom Heaton will look to leave the club this summer.
Of the three senior outfield players included, Mata is out of contract and leaving, while Jones and Eric Bailly want to move to seek more regular first-team football.
Hopes are high for all four youngsters on the bench, but at least a couple are likely to head out on loan next season. Fernandez needs some first-team exposure, while Hannibal has to either be a regular in Ten Hag's squad or spend the season on loan, while the same could be true for Shoretire.
At 17 Garnacho might well continue his development at Carrington but his presence in the first-team squad next season is likely to be fleeting, so of those nine substitutes last night maybe only two or three will be regularly available to Ten Hag in his first season at the club, while one of last night's starters, in Nemanja Matic, is also heading for the exit door this summer.
Ten Hag and football director John Murtough will focus on strengthening some key areas this summer, with central midfield clearly in need of an upgrade, while Rangnick has already signalled the intention to sign a new forward.
Bringing in five new players this summer would have to be considered a very good window, given United won't be able to offer Champions League football and have rarely been that active before. If they can achieve that they should head into their first season under Ten Hag with a better team than this season.
But if the task is to be able to match the likes of City, Liverpool and Chelsea, then United need a serious improvement in squad depth as well and that could take several transfer windows to achieve.
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