Nicky Cadden and John McAtee gave the Tykes an early 2-0 lead, before McAtee’s sublime chip tripled Barnsley’s advantage inside 30 minutes.
The Hornets were vastly-improved in the second half – with livewire striker Daniel Ajakaiye coming close on three occasions – but the Isthmian Premier outfit couldn’t find the goal their attacking play so richly deserved.
Di Paola said” I’m really proud. I would have liked to have done better, that’s the main thing. As with everything, you just want to do better.
“It was a great occasion. Both sets of supporters were amazing. Barnsley’s people have been magnificent both times we played them. What a great club.
“It’s just a shame we couldn’t have given them a goal to leave the stadium with.”
McAtee’s second goal effectively killed off any hopes of a famous Horsham upset.
Di Paola admitted the Hornets were like ‘rabbits in the headlights’ in the first half but paid tribute to his players for an excellent second 45 minutes.
He added: “The first ten minutes just killed us a little bit. We were like rabbits in the headlights. We just didn’t quite get to grips with what we tried to work, and before we could correct it we were two down.
“It was a mountain to climb against such a good team. I was really disappointed, but that’s on all of us and the management team.
“I thought we played some good stuff at times. In the second half we showed that we can perform.
“Credit to the boys, when you’re 3-0 down like that you can fold and it can be sixes and sevens against such a good side.
“But the boys showed good bravery to keep passing the ball and on another day, maybe you get a goal.
“That’s the frustrating thing. It destroyed us, those opening stages [of the first half].
“It’s disappointing because the boys have worked so hard, we just couldn’t quite get to grips with it early on.
“There’s a little bit of regret because they’ve had four or five chances an punished us.
“If you weather that opening period, then we could have grown into the game like we did. But when you’re 2-0 down at that period, you’ve got a mountain to climb.”
A club record attendance 3,000 spectators packed the Camping World Community Stadium for tonight’s Cup clash with the Tykes.
Di Paola said the attendance showed the undoubted potential of the club. The Hornets boss also hailed to all the club’s volunteers for all their hard work on a historic night for Horsham Football Club.
He added: “We’re growing all the time. Our attendances are growing almost week on week.
“It’s a good place to be. Most of the time we play attractive football and we have some talented boys here.
“People who come here come two or three times and are hooked on it.
“We hope some of the ones who have come here for the first time come back. If there’s one positive from tonight, we’ve put on a great occasion.
“Hats off to all the volunteers who have been running round for three or four days trying to get this all sorted. It shows the potential of the whole town that we got 3,000 here. We could have got 6,000, there was so much interest.
“Maybe we can get back here one day, but now we need to kick on.”