Crawley Town head coach Harry Kewell blamed 'silly mistakes' for his side losing the Parafix Sussex Senior Cup final against Brighton under-23s
Holding a 1-0 lead through a 68th minute goal own goal, Reds conceded two goals in the last eight minutes scored by Albion's James Tilley and Josh Kerr.
Crawley seemed to be on track for victory when Enzio Boldewijn's cross caused Albion's Kerr to put the ball in his own net.
Kewell admitted: "Staying in League 2, getting to a nice position, breaking a lot of records, especially at home, doing the majority (of the season) without a striker as well, so for us it's been a tough season.
"Finishing at Mansfield, where we gave everything, to come here, playing a young team who would be fully up for it; it's a big competition for them.
"It's more about us being professional and having mental strength. We dealt with that.
"We can't afford to make mistakes. Unfortunately we made two silly mistakes, but from the second mistake we got out of it through a good save (a penalty save by goalkeeper Yusuf Mersin)..
"So it was disappointing, but credit to Brighton - they ran, they hassled, they had a couple of chances and congratulations to them."
Kewell revealed a training ground accident 24 hours before the match had a major impact on his already depleted squad.
Defender Mark Connolly and striker Panutche Camara were both sidelined through injured caused in the incident, leaving him short of players and only able to name two on the bench.
He admitted his lack of numbers caused him a problem in seeing out their lead at the end of the game.
It was during the frantic last few minutes that Brighton scored both their goals.
Kewell said: "Unfortunately we had a collision, one (player) broke his foot and one had a swollen ankle; so that took two of my starters out.
"I took a risk with a couple of players who haven't played all season, which is difficult, so the fitness isn't there.
"And you can see if I had two or three more players I would have made the substitution and brought on fresh legs, which would have made a huge difference.
"But you have to deal with what you are dealt with. Congratulations to Brighton, they played a good game and we have to move on."