Ireland had no-one near him when he suddenly felt unwell.
He was promptly substituted by Mark Hughes but when his symptoms failed to improve, he was taken to Wythenshawe Hospital for exhaustive tests.
He was eventually given the all-clear, but told the Manchester Evening News: "Thankfully it wasn't too serious because at the time I thought that was the end of me.
"I don't know what it was. I have had every test that there is and I still don't know but it was a bit of a strange scare.
"It took me a while to get right but I am back on track. Everything is looking positive."