Now Alex McLeish has challenged the Aston Villa midfielder to recapture his "world-class form" of two years ago.
Ireland's days at Villa looked numbered when loaned out by the then manager Gerard Houllier to Newcastle for the second half of last season.
But the slate has been wiped clean for Ireland since McLeish replaced Houllier in mid June.
Alex McLeish: "Stephen has a lot to offer. A couple of years ago that guy was verging on world-class stuff (with Manchester City) It's about him recapturing that kind of form.
"We will try our best. We will keep trying. We're not about to give up on big investments on Stephen. He's a very important member of the squad."