The Rats tour manager Mark Welch is a Crawley Town fan and arranged for the two parties to meet at the Rats rehearsal studio.
And in a brilliant video with manager John Yems, Geldof said they were there to try and build a new clubhouse for Crawley Town as he pointed to a dilapidated barn.
The Rats are performing at the Hawth on Tuesday, October 12 (tickets on sale from Hawth box office soon) and Yems and a few of the Reds players will be there.
In the video, Geldof said: "This is a public service announcement here at Crawley Town FC and we are here to try and help the team build a better club house and as such we will be playing Crawley at the Hawth which is a fabulous place.
"I used to live around here. It’s not like coming home but it is like going back. I used to drive machines that built the Merstham interchange. I used to live in Godstone.
"So dude, home boy, come and check us out at the Hawth Theatre."
And why are they playing at the Hawth? Geldof said: "We have some big gigs coming up, we are rehearsing in this place near Crawley so it’s great to go down the road, set up in a great theatre where we can put all the gear up and play crazy and not worry about the big crowds or anything.
"Just a great home crowd, [to John Yems] just like you guys play in front of."
Geldof added: "The Boomtown Rats support Crawley Town FC - come on guys let’s build a new club house and let’s score a few goals this season."
And when asked if Yems and his players were going along to the gig, Geldof said: "They are the support act, they will be singing ‘Crawley, Crawley what a mega team’ don’t you know it?!’