Red Bull Salzburg's attacking midfielder Brenden Aaronson became the club's first signing of the summer window at the end of May, before right-back Rasmus Kristensen followed him from the Austrian side around two weeks later.
Spanish midfielder Marc Roca then completed his move to West Yorkshire from German giants Bayern Munich on Friday, taking Leeds' total spending to a figure in the region of £45m.
Further additions are set to be made by Marsch, although star players Raphinha and Kalvin Phillips could be heading for the exit door amid links with a number of top European clubs.
Here, Sports Mole takes a look at how Leeds could line up next season with Aaronson, Kristensen and Roca in their first XI, along with the current group of players at the club.
When Jesse Marsch took over from Marcelo Bielsa in February, the American began his reign with a 4-2-2-2 formation - a system he used frequently during his time with Salzburg - but towards the end of the campaign he switched to a 4-2-3-1 formation, which could be used again on a regular basis in the new season.
Illan Meslier is one of the first names on the teamsheet as he is still regarded as the club's first-choice goalkeeper, and protection in front of him is set to be provided by centre-backs Liam Cooper and Diego Llorente. Both Robin Koch and Pascal Struijk will also compete for a place in central defence.
Junior Firpo is set to start regularly at left-back now that Stuart Dallas has been ruled out for a lengthy period with a knee injury, while Luke Ayling faces stern competition from new arrival Kristensen for a place at right-back. The latter - who recorded 10 goals and eight assists for Salzburg last season - could become a key attacking outlet for Marsch's side down the right, which will likely see him get the nod over Ayling.
At the time of writing, both Raphinha and Kalvin Phillips are still at the club, but should the former leave this summer, Welshman Daniel James would be the most likely candidate to operate on the right flank, while Jack Harrison will be hoping to build on an impressive 2021-22 campaign with regular starts again on the left wing.
Some reports in the media have suggested that Roca - a left-footed deep-lying playmaker - has been signed as a replacement for Phillips, but as things stand both players could play together in Marsch's midfield. Mateusz Klich and Adam Forshaw, however, will battle for a place in centre-midfield if Phillips does decide to seek pastures new.
Aaronson is likely to operate in a number 10 role, where the 21-year-old predominantly featured for Salzburg last season, scoring six goals and providing 10 assists in 41 appearances. However, he is also capable of playing in a deeper midfield role or on the flanks.
Both Aaronson and Rodrigo could end up battling with each other to start in the same position, but considering the former was Marsch's primary target heading into the summer window, the American is expected to play regularly under his compatriot.
Patrick Bamford will be hoping to avoid another injury-plagued season, after featuring only 11 times in 2021-22. Having the 28-year-old fully fit next season will almost feel like a new signing for the Whites, and when available he is still deemed as their first-choice striker to lead the line. Rodrigo, Joe Gelhardt and Sam Greenwood will all provide healthy competition for Bamford in the final third.