The Red Devils are believed to be exploring the possibility of luring the 19-year-old to Old Trafford, while a number of other top European clubs including Chelsea, Liverpool, Newcastle United and Real Madrid are also keeping tabs on his situation.
After scoring 21 goals in 29 games while on loan with Austrian second-tier side FC Liefering in 2020-21, Sesko returned to Salzburg and featured regularly in the first team last season.
The 6ft 4in Slovenia international scored 10 goals and provided seven assists in 37 appearances for the Austrian Bundesliga champions in 2021-22, and he also gained experience in the Champions League.
A recent report claims that Man United have made contact with Salzburg to discuss a possible transfer for Sesko to Old Trafford this summer.
According to i, representatives of both Chelsea and Newcastle have met with the player's agent Elvis Basanovic, although Salzburg are keen to keep hold of the teenager unless they receive an offer of at least £45m.
Any interested parties are thought to be at risk of seeing Sesko's valuation rise should he remain at Salzburg for the 2022-23 season.
A recruitment source told i: "It's probably a summer too early for [Sesko], but every club is looking at the price Liverpool paid for Darwin Nunez and thinking it might cost them an extra £20m if they wait another 12 months."
Basanovic has previously stated that Sesko attracted interest from several "really big clubs" before he decided to join Salzburg in 2019.
"We had a lot of offers from really big clubs. Had we decided on the money, Benjamin would have moved to England or Italy," Basanovic told SPOX.
"But we decided to look at the bigger picture and the Salzburg project. The biggest clubs in Europe tried to get him. The interest in him was huge; I have never seen anything like it before.
"Salzburg has given Benjamin a path. Here, he can develop. The people in charge really wanted him, which was important to us. Here he also has a greater chance of playing for the first team sooner or later.
"Benjamin is one of the greatest talents of his age group in Europe. He has an incredible body, is tall, fast, has great jumping ability, is technically gifted and his greatest strength is his finishing."
Man United are believed to be in the market for at least one attacker before the September 1 deadline, with Sesko one player on their radar, and their recruitment could depend on the future of Cristiano Ronaldo.
The 37-year-old made his first appearance in pre-season when he played the first 45 minutes of the 1-1 draw with Rayo Vallecano on Sunday.
However, Ronaldo is still 'desperate' to secure an exit away from United this summer and is allegedly hoping to leave by the end of the week, with his agent Jorge Mendes holding talks with potential suitors who have qualified for the Champions League.