After going a goal behind early on, Horsham equalised through Shamir Fenelon’s excellent finish before James Hammond gave the Hornets the lead from the spot.
Barnsley overturned the deficit to make it 3-2 before Richards tapped home late on to seal a famous cup result.
But who stood out for Horsham? Here are Sam Pole's ratings from the game.
17. Tom Richards
After coming on a second half sub Richards was the hero late on, to tap home from a Lucas Rodrigues cut back to level it up for Horsham at 3-3. His energy down the left hand side was superb and when the Hornets needed some defensive stability late on with Barnsley pushing the winner, was excellent at providing cover for Harvey Sparks. 9/10 Photo: John Lines
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