Richards played his part in a superb Palace shutout, while goals from Jean-Philippe Mateta, Tyrick Mitchell and Ismaïla Sarr at the other end gave the Eagles a healthy first leg advantage to take to Tuscany next week.
The Serie A side did push numbers forward in a bid to get back in the game, but Richards along with defensive pair Jaydee Canvot and Maxence Lacroix, barely put a foot wrong all night.
After the win Richards told TNT Sports: "Of course we want to get to the final, but we understand it's one game at a time.
"So I think it'd be dumb to say that we're already looking at the next opponent [in the semi-final].
"Again, we have a whole other leg still to play and it's going to be a hostile environment in Fiorentina. We understand that we have to go and get a win there.
"We always focus on making sure that we maintain a clean sheet because it allows the people up front to do what they need to do.
"Defence isn't always, you know, the most beautiful thing to do! But whenever you get a clean sheet, it always helps the team."