The Omani international said his time on loan at the DW Stadium last season renewed his faith in himself and he leapt at the chance to return on permanent terms.
Al Habsi signed a four-year deal with the Latics after a deal was eventually struck — believed to be for £4million (Dh23.75m) — after weeks of negotiations over a fee.
Al Habsi was Wigan's player of the season last term and he revealed, after four years as the understudy to Jussi Jaaskelainen at Bolton Wanderers, it was the first time he felt like a real professional footballer.
"To come from Bolton on a season loan and get player of the year was great - especially as it was the first time in my life I had played like a professional in terms of every week," said the 29-year-old.
"The thing with Bolton was Jussi was there but I showed myself 100 per cent when Jussi was injured and I got my chance and so everyone knew what I had.
"At my age this is the time to play week after week and I think I have come to the right club.
"Now it is my job to show myself more than I showed last season."
Wigan manager Roberto Martinez made Al Habsi's signature his priority this summer and although there was a time when it seemed the deal was deadlocked, the Spaniard was confident it would go through.
"I wouldn't say it was a predictable signing," said the Spaniard. "When you know that something could happen that is often the hardest one to achieve but I am extremely pleased Ali was focused to come here and we have signed a player we wanted.