Currently managing RB Salzburg, Marsch has previously managed two clubs in MLS as well. He has also been an assistant manager of the USA national side. At Salzburg, his current points-per-match tally stands at 2.12, which is pretty impressive (as per Transfermarkt).
He has recently made it clear that it is an honour to have been linked with Celtic, saying that both parties would need to be on the same wavelength for him to take over.