The Red Devils have lost Christian Eriksen for the next three months due to an ankle injury that the Dane sustained in the weekend's FA Cup win over Reading, forcing the club into last-minute transfer action.
Both Man United and Chelsea were said to have enquired about a move for Bayern Munich midfielder Sabitzer, who has struggled to make a name for himself at the Allianz Arena in the last 18 months.
Erik ten Hag's side moved quickly to strike a straight loan deal for the Austria international, who has been pictured at the airport ahead of his temporary switch to Old Trafford.
In their search for midfield reinforcements, Sky Sports News claims that Man United were offered no fewer than three separate central midfielders, including Lyon's Aouar.
The Frenchman, who was heavily linked with a move to Arsenal in 2021, is out of contract with Lyon at the end of the season and is free to discuss pre-contract terms with foreign clubs.
Aouar has experienced a sharp downturn in fortunes over the past couple of years, though, and the 24-year-old only has one goal to his name from nine appearances in the 2022-23 campaign.
Nottingham Forest were also believed to have been in talks to sign Aouar over the summer, but Man United were also offered as many as three La Liga-based lynchpins.
Former Real Madrid creator Isco has been without a club since leaving Sevilla in December, having spent just half a season with Jorge Sampaoli's side, scoring once and providing three assists in 19 games.
The 30-year-old was initially on the verge of a deadline day move to Bundesliga outfit Union Berlin, but a deal collapsed after he had already passed his medical due to contractual disagreements.
Explaining Isco's failed move to Bild, Union manager Oliver Ruhnert said: "We would have liked to see Isco with us, but we have our limits. These were exceeded today, contrary to previous agreements, which is why the transfer will not take place."
Finally, Atletico outcast Saul was understood to be another option for the Red Devils, having also seen his influence wane under Diego Simeone in recent months.
Man United were pursuing a deal for the Spaniard throughout the summer of 2021, but he ended up joining Chelsea on loan and endured a disastrous spell with the Blues.
Saul has since scored one goal and provided one assist in 22 games for Atletico this season, although he has only started six La Liga matches.
Saul's teammate Yannick Carrasco was also reportedly offered to Man United, but the Red Devils have opted against moving for a new winger after retaining the services of Facundo Pellistri and Anthony Elanga.