Liverpool's best-in-class Champions League record this season now counts for nothing — it arguably never counted for much, given that the reward has ended up being a brutal match-up with PSG. Regardless, the simple equation for Arne Slot now is that he must win the tie in order to progress, something he must do while missing four players.

While the league phase struggles of PSG, Real Madrid, and Manchester City were enjoyable to watch, it always meant that one of the early high-flyers was likely to be handed a tough assignment in the last 16. The fates smiled on Barcelona, who landed a tie against Benfica on the favorable side of the draw while handing Liverpool one of its trickiest tests of the campaign.

For it is not even an out-of-form PSG side that Slot is facing. It might have taken a bit of time to find its feet this season, but the French juggernaut has now won the last 10 in all competitions, a record which could even pose a problem to Mohamed Salah's seemingly unstoppable progress.

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Salah will surely be key to Liverpool's hopes. He knows that good performances in the latter stages of the Champions League will further strengthen his growing case for the Ballon d'Or.

Fortunately, he has been indestructible this season. But Slot does not quite have everybody at his disposal heading into the first leg of the encounter.

Joe Gomez

It has been a tough season for Joe Gomez. Injuries have prevented him from ever really forcing his way into Slot's plans.

After struggling to find initial favor, Gomez began to battle his way into the setup and started six consecutive Premier League matches throughout December in the absence of Ibrahima Konate. But in the last of those, his hamstring gave up on him.

Liverpool was cautious with his return, but it was not enough. Gomez's long-awaited comeback against Plymouth lasted barely 10 minutes, before he was forced off once again.

The defender has now undergone surgery. Slot has expressed hope that he could be back before the end of the campaign, but he is a long-term absentee and will miss both legs of the tie against PSG.

Conor Bradley

It would have been very interesting to see the side Slot might have named for this fixture if Conor Bradley had been available. Injury to the right-back has saved him a dilemma.

Bradley has picked up where he left off last season, leaving an equally favorable impression on Slot as he did on Jurgen Klopp. However, the Northern Irishman will not be available to face PSG, having also suffered a hamstring issue.

Injuries have been a little too common for Bradley, but that's about the only blot on his copybook. The question of exactly how far he can go is more pertinent than ever amid continued question marks over the future of Trent Alexander-Arnold.

The duo are not the same player by any means. Bradley does not boast the technical excellence of Alexander-Arnold, lacking the same vision and execution that marks out the number 66 as a generational kind of talent.

But under Slot's system, Liverpool is less reliant on that kind of brilliance from full-back. An industrious, diligent player with an eye for contributions in the final third can build up just as much credit in the bank.

Having seemingly improved on his defending, Alexander-Arnold's contributions at the back have once again been under the microscope in recent weeks and months. Facing the prospect of tricky customers like Bradley Barcola and Desire Doue, might Slot have been tempted to opt for Bradley if the choice had been there?

Tyler Morton and Amara Nallo

Admittedly, Slot would have been unlikely to call upon either Tyler Morton or Amara Nallo against PSG, but now he will not even have the options available to him. Both have already featured in the Champions League this season but will have to watch from the sidelines at the Parc des Princes.

In Nallo's case, that is a direct result of his previous Champions League outing. The youngster suffered a nightmare debut, receiving a red card against PSV, which means he is now suspended.

Morton also played that night. But the midfielder was playing through a shoulder injury that he had sustained in December.

Liverpool managed the issue throughout January amid the possibility that Morton may leave during the transfer window. But once it became apparent that a move was not forthcoming, he was sent for surgery and is now expected to miss the remainder of the season.

The hope is that the decision will leave Morton in peak condition come the summer. It's anticipated that he might then exit the club in search of minutes, although Liverpool will insist upon its valuation being met.