Horsham led by 14 points at half time, with tries coming from Aaron Linfield, Rich Tredgett, Jordan Smith, Ed Mannhardt and Jonny Goward.
But they were edged out after an unstoppable Old Northamptonians second-half performance in the Papa Johns Men’s Regional 2 Championship.
Quins’ star and Horsham coach Chisholm believes the side gave their travelling supporters a performance to be proud of despite their heart-breaking defeat.
“It’s been an amazing day for the club, both teams were so well supported,” said Chisholm.
“From a Horsham point of view, you could see how much it inspired the town and younger generations supporting the boys, they were delighted to be here and really pleased with how they played.
“We spoke about it before, it’s about enjoying the day, but also putting out a performance which we can be proud of and I think everyone is immensely proud of how they did.”
Horsham came out the stronger of the teams with scrum-half Linfield crossing early on before the Midlands side levelled the scores after 10 minutes.
Horsham then found a purple patch in the second quarter of the match, dotting down twice, first through Tredgett and then flanker Jordan Smith as they pulled into a 21-7 half-time lead.
But they were on the wrong end of a remarkable second-half turnaround, which saw Old Northamptonians lead by 12 points with just ten minutes left on the clock.
Mannhardt scored to give Horsham late hope and Goward scored their fifth at the death by which point Old Northamptonians had already secured the win.
“We made too many mistakes in the second half and didn’t control the field position like we did in the first half,” said Chisholm.
“Ultimately if you give good teams opportunities to score, they’ll take them.
“We said at half time that if we won the first 10 minutes of the second half we would probably go on to win the game, but we lost that period because of the territory battle and two quick tries killed us.
“Once you lose momentum it’s so hard to wrestle it back.”
The inaugural season of the Papa Johns Community Cup may have ended in heartache for Chisholm’s team, but he lauded the new initiative which was introduced to provide a crescendo to the end of the grassroots season.
“It’s a huge incentive after the league season,” he said.
“It’s been a great competition, we’ve thoroughly enjoyed ourselves and we’ve really bought into what it’s about.
“For any rugby player, playing at Twickenham is the pinnacle, I’m so proud that Horsham have been able to achieve that and put in a performance they can be proud of.”
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