Hyypia scored the winning goal after 49 minutes of the clash at Windsor Park, but was not pleased by the playing conditions on the night.
He said: "I have not played in fog like that and I wasn't very happy about it. But it was a nice moment for me to get the goal.
"It's not something I do regularly at club level but I've now managed one or two for Finland.
"The Irish played as we expected. They were a very typical British team and fought very hard."
