Bayern Munich s Austrian midfielder Marcel Sabitzer celebrates scoring the 5-0 goal during the German first division Bundesliga football match between FC Bayern Munich and SC Freiburg in Munich, southern Germany on October 16, 2022. AFP
Eriksen could miss most of the remainder of the season because of an ankle injury, sustained during United's 3-1 win against Reading in the FA Cup on Saturday.
That prompted the Premier League club to look for midfield reinforcements before the January window closed, with Sabitzer flying in from Germany to sign a deal until the end of the season.
``Sometimes in life you have to make quick and important decisions,`` Sabitzer said. ``From the moment I heard about this opportunity I knew it was right for me. I am a competitive player; I want to win and help the club achieve its aims this season.''
Sabitzer has won 68 international caps for Austria and played 24 times for Munich this season.
United said Eriksen will be sidelined for ``an extended period'' _ likely until late April or early May.
The Denmark international has become a key figure under United manager Erik ten Hag, making 31 appearances this season.
The former Tottenham and Inter Milan player suffered a cardiac arrest on the field at the European Championship in 2021 and needed to be resuscitated with a defibrillator. He had a cardioverter-defibrillator fitted and made his return to top flight soccer a year ago when he joined Premier League club Brentford.
His performances for the London club led to a move to United last summer.
Ten Hag on Tuesday said it would be difficult for United to replace Eriksen's influence.
``Another player will always fill it in a different way but that doesn't mean you have to be less successful,`` he said. ``It's quite clear that Christian Eriksen brings top quality to our squad and especially he has some specifics that are hard to replace.
``For instance, his impact in the final third with the final ball.''
The deal for Sabitzer gives Ten Hag more options for the remainder of the campaign, with United still aiming to qualify for the Champions League as well as competing in the League Cup, FA Cup and Europa League.
``Marcel is a player that we have watched for a long time. The opportunity arose quickly, and we knew that he was someone with the ability and character to make an impact,`` United football director John Murtough said. ``He adds further quality to our squad and experience to the dressing room.''
United plays Nottingham Forest in the second leg of the League Cup semifinals on Wednesday, leading 3-0 after the first game.
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