The USA international joined the Citizens from MLS outfit Columbus Crew in the summer of 2019 before immediately joining German side Fortuna Dusseldorf on a season-long loan deal.
Steffen was then integrated into Pep Guardiola's first-team squad for the next two seasons, but struggled for regular game time and was forced to play second fiddle behind first-choice goalkeeper Ederson.
After featuring just nine times in all competitions for City in the 2021-22 campaign, Steffen joined Championship side Middlesbrough on loan to gain regular first-team football ahead of representing the USA at the 2022 World Cup.
However, a dip in form and a knee injury ultimately prevented Steffen from earning a call-up to Gregg Berhalter's national team squad, with Arsenal's Matt Turner taking the number one jersey for the tournament in Qatar.
Steffen has since responded well to that disappointment at the end of last year, and has been an influential member of Michael Carrick's promotion-chasing Middlesbrough side who currently sit third in the Championship table.
The shot-stopper, who has been integrated back into Berhalter's USA squad for this month's international break, is under contract at Man City until June 2025, but he does not intend to return to the Etihad this summer.
"I don't think I'll go back. No, I want to be playing," Steffen told the Philadelphia Inquirer. "Although I had a great time at City and I love those guys, and obviously an amazing club, I don't really have any plans to go back."
Steffen has opened up on how faith helped him through his struggles at the beginning of the season and believes he now has a greater understanding of who he is as a goalkeeper and a person.
"It was tough. God tested me. It definitely wasn't easy, as you can imagine — just surprising and, yeah, just not what I expected," Steffen added. "It wasn't part of my plan, but I know that God ultimately has a greater plan and path for me.
"I think this year has brought me some peace and understanding of who I am and what kind of goalkeeper I am. I've dived heavily into my faith, and that's helped as well. Confidence is good, still striving for bigger and better heights, and bigger goals and dreams."
It remains to be seen whether Steffen - who has kept nine clean sheets in 35 Championship matches - will consider joining Middlesbrough on a permanent basis in the summer.
Man City responded to Steffen's temporary departure last summer by recruiting Stefan Ortega on a free transfer and he has since featured as an understory to Ederson, while Scott Carson continues as third choice in Guardiola's squad.
Steffen is in contention to start for the USA when they face Greneda in a CONCACAF Nations League match on Saturday.