The 22-year-old American has spent most of pre-season with the club after arriving in the country a month ago but had to wait for international clearance to be formalised before confirming his signature.

Born and raised in East Northport, New York, he spent last season in Germany with TB Uphusen.

Prior to this he had four years at Temple University back in the USA but has had two spells in English football, one with Fleetwood Town during this time.

Mueller, an athletic attacking left-back, has impressed during his time in Southport and is looking forward to the challenge ahead. He told https://southportfc.net: “This club has great ambition and high expectations, but everyone I’ve met have treated me like family. It’s an exciting opportunity in my career and it’s every player`s dream back in the States to play in English football at a high level.”

Manager Liam Watson said: “Stefan has come back to the UK to prove himself after finishing his degree at Temple University. He was highly recommended by my former Manager from when I played out in the US, so we offered him the chance of a trial and we have been very impressed with his ability, the way he has settled into the squad and his desire to play for Southport.”