Jurgen Klopp has confirmed to the media that Joel Matip has a torn ACL. The serious knee injury will likely keep him out for the rest of the season.
Matip was known to be injured but Liverpool hadn't revealed the extent of it. It's now known to be a bad one, to say the least, and the sense is that the Cameroonian is done for the season.
And with that, he might be done for Liverpool. Matip's contract is up at the end of the season, while he's also now 32 - it makes little sense for the Reds to renew it at this stage.
Of course, it was up in the air whether Liverpool would renew it anyway. Now Matip may not return fully until midway through next season. It'll also be very difficult for the defender to recover to his best - he may never do so.
Thus Liverpool have an enormous - and emotional - decision coming up. Matip has been at the club since 2016, winning everything as a regular partner for Virgil van Dijk.
This, however, could be the end of his time at Anfield.
As for this season, Liverpool also have some big decisions. Matip missing would leave Virgil van Dijk, Ibrahima Konaté and Joe Gomez as the senior centre-backs. Gomez, however, is also the cover at right-back and, with Andy Robertson out, left-back, too.
Konaté's injury record is concerning on top of that, leaving Van Dijk as the only real constant in the middle of defence. So here comes the decision.
Liverpool could dip into the January market to find someone new. They have been linked with players already, and you can expect those links to increase after this.
There's also Jarrel Quansah, who has been seriously impressive when called upon this season. Do Liverpool put full faith in him for the rest of the season? Everyone should find out next month.