Gretna wrecked Dundee United's hopes of going top of the table with their 3-2 victory yesterday.
Allan Jenkins headed the historic winner four minutes from time after Lee Wilkie had equalised following David Cowan's first-half double.
And Irons believes the victory over third-placed United at Fir Park shows they can compete in the top flight.
He said: "We were getting a bit sick of being patronised by people saying 'Poor Gretna, they will get a win one day'.
"That stirs us up. We are not here just to make up the numbers. And I think we have seen today we can compete.
"We are a wee club. I hear people commenting that we don't bring much to the party. What do they want? Ten thousand people coming from Gretna to watch games?
"We are here because we have proved we deserve to be here and we will keep striving to compete."
The match saw midfielder Paul Murray replace Chris Innes as captain, although the former Dundee United defender retains the club captaincy.
But Irons played down the move and insisted it was his decision and not the brainchild of director of football Mick Wadsworth.
"It's not anything against Chris," Irons said. "He has been a magnificent leader and an inspirational captain.
"We just felt he needed a bit of help. I'm of the old school, I think there should be 11 captains and today there were.
"He (Innes) is obviously disappointed but he is a professional and he accepted it and today's performance showed he didn't let it affect him.
"It was a decision made by me for the right reasons. I don't see it being a big issue."
