Liverpool defender Conor Bradley will miss the rest of the season with a significant knee injury sustained in Thursday's goalless draw at Arsenal.
Bradley will undergo surgery in the coming days to repair bone and ligament damage, but it is not an anterior cruciate ligament (ACL) injury.
Bradley will miss Northern Ireland's World Cup play-off tie with Italy in March, but it is unclear whether he would be fit in time for this summer's World Cup should Michael O'Neill's side qualify through the play-offs.
Liverpool revealed there is "no timeframe being placed" yet on the 22-year-old's return.
Confirmation of Bradley's injury comes after Arsenal forward Gabriel Martinelli had pushed the defender as he lay injured on the ground before being stretchered off.
Martinelli was booked by referee Anthony Taylor following the stoppage-time flashpoint with the winger , which provoked anger among Liverpool's players.
But the Brazilian, who apologised for his actions on social media after the game, from the Football Association, with the matter considered dealt with as it was seen at the time by Taylor.
Martinelli returned to action in Arsenal's 4-1 win over Portsmouth in the FA Cup third round on Sunday. After the match, Mikel Arteta praised the response to the incident from Arne Slot, who placed no blame on the forward.
"I must say I think the way Arne Slot spoke after the game, was brilliant. He knows how the players feel about themselves, how they feel about their colleagues.
"That is somebody who knows the game really well, and how you react in a certain way. There was no intention to damage a player or not to respect a player."
Bradley had made 21 appearances this season, having missed a number of matches with a hamstring problem.
It leaves Reds head coach Arne Slot with Jeremie Frimpong, who has had his own injury problems since joining from Bayer Leverkusen in the summer, and Joe Gomez, himself only just returning from a hamstring issue, as cover, but neither can be considered a genuine right-back.
Slot has had to utilise midfielders Dominik Szoboszlai and Curtis Jones in the position this season.
Your Site' Roy Keane was critical of Martinelli's actions, labelling them as "an absolute disgrace".
"It's not good. We know football, the player is a good lad," he said.
"Throwing the ball at him, standing over him and getting a little knee on him. He tries to force him off.
"That behaviour is an absolute disgrace. He's a good boy to roll over himself. Hopefully, Martinelli will have a look at it and hopefully, he'll apologise for it. Not good stuff that."
Daniel Sturridge added: "It's disappointing to see. There's passion and there's being a winner, there's wanting to help your team-mates, but you've got to be respectful as a footballer.
"Injuries are never a nice feeling. Martinelli is thinking time wasting but you've got to be self aware enough to see the guy is down. You've been there before.
"It's disrespectful. It's probably worse than disrespectful."
Former Premier League referee Dermot Gallagher on Your Site News' Ref Watch:
"If the players leave it alone, it's easier for the referee to deal with Martinelli. Once everyone else gets involved, it ramps up everything else.
"I think what Martinelli does gets diluted and in many ways, they have helped him stay on the field."
On if Martinelli should've received retrospective punishment: "I think not.
"He's been given a yellow card for his actions. If the players leave it to the referee, he's got a different landscape to deal with. When they all pile in, he's got to check everybody else.
"I think there's not quite enough there [for it to be a red card]."
